Literature Review

Dr Lyn-li Lim joined VICNISS in early 2019. She is an infectious diseases physician with post-graduate training in epidemiology, public health and medical administration, and holds a co-appointment as a physician and antimicrobial stewardship lead at a public health service in Melbourne.
See below for her latest literature review:


December 2023 - Intervention strategies for prevention of CAUTI 

Gray et al (J Hosp Inf 2023) have published a pragmatic review of interventions to prevent CAUTI in hospitalised patients. Catheter-associated UTIs (CAUTIs) account for 70-80% of hospital-acquired UTIs. How best to operationalize guidance to prevent CAUTIs remains a challenge. This study aimed to map and summarize the peer-reviewed literature on model-of-care interventions for the prevention of CAUTIs in adult inpatients. 

Researchers identified 70 articles comprising of single component interventions (n=19) or multi-component (n=51). Single component interventions included: daily rounds or activities (n=4), protocols and procedure changes (n=6), reminders and order sets (n=5), audit and feedback interventions (n=3), and education with simulation (n=1). All studies used the definition based on CDC’s NHSN guidelines which required fulfilling criteria for UTI (with clinical and microbiology criteria) and where an IDC was in place or within 2 days of removal.  Two were RCT; (1) a cluster randomised crossover trial where the intervention was use of a catheter tag significantly reduced mean catheter durations but only in the non-ICU cohort (2) stepped-wedge RCT where surveillance  data was fed back as a performance measure to hospital staff during education sessions (e.g. with intervention period 1, 3 sessions delivered over 2 months) found no significant effects on mean catheter duration or CAUTI rates despite staff reported uptake of CAUTI prevention measures. Overall, daily catheter reviews and protocol and procedure changes demonstrated the most consistent effects on catheter and CAUTI outcomes. Audit and/or feedback was incorporated into 47 multicomponent interventions. Analysis of the multi-component intervention studies suggests that education may need to target nurses and medical students, not just physicians, to reduce CAUTI rates. 

The researchers state that they undertook this research as “no one policy, programme or intervention will always work, all the time, for everyone”. This review offers a menu of intervention options for local decision makers to consider, with consideration given to local context as to what will work for whom and under what circumstances. A limitation of this review was that interventions using education alone were excluded. This was on the advice of the working group where it was felt that these are difficult to implement and maintain long term and have limited value when implemented alone. A response letter to this paper proposes that limitations to the search strategy potentially narrowed papers (and intervention strategies).  

December 2023 - Can Candida auris be dispersed through air? 

Didik et al provide a case report (J Hosp Inf 2023) of a C. auris nosocomial outbreak.  This multidrug resistant fungus’ mode of transmission has been reported to be via direct contact. Studies have suggested potential short-distance air dispersal during high turbulence activities, but evidence of for longer distance air dispersal is scarce. 

This is a report describing a C. auris nosocomial outbreak involving two hospital wards with an open-cubicle ward setting. On the 17 September, 2022 a urine sample from a catheterised patient grew C. auris. The patient had been an in-patient since July 178th with multiple transfers between the two hospitals, and on multiple open cubicle wards.  To investigate, samples were taken from patients, ward surfaces (frequently touched items and non-reachable surfaces) while settle plates were used for passive air sampling. 

As expected, C. auris was expectedly identified in samplings from frequently touched ward items. Unexpectedly, it was also isolated in (1) two samples from ceiling supply air grilles which were 2.4-meter-high and inaccessible by patients (2) one sample from a corridor return air grille as far as 9.8 meters away from the C. auris cohort area (3) two passive air samplings were positive, including one from a cubicle with no confirmed cases for 4 days, suggesting possible air dispersal and persistence of C. auris. Whole genome sequencing confirmed clonality of air, environment, and patients’ isolates. 

The authors conclude that this is the first study to demonstrate potential long-range air dispersal of C. auris in an open-cubicle ward setting. They propose that ventilation precautions and decontamination of out-of-reach high-level surfaces should be considered in C. auris outbreak management. 



October 2023 - Search for a universal influenza vaccine – one step closer

The current effectiveness of the seasonal influenza vaccine ranges between 10 and 60%, depending on how well vaccine strains match to circulating strains. These vaccines are subject to ongoing antigenic changes known as “drifts”. For influenza A, these drifts can be pronounced each season, and much more gradual for Influenza B.  Seasonal influenza vaccines provide virtually no protection against novel pandemic strains.

In 2018, the US National Institute of Allergy and Infectious Diseases (NIAID) identified that influenza vaccines that were more broadly and durably protective were needed (J Infect Dis. 2018; 218 (3): 347-354).  It identified that the focus of work in this area should be to create a universal Influenza vaccine that would:

  • Be at least 75% effective against symptomatic infection
  • Protect against group I and group II influenza A viruses (influenza B would be a secondary target)
  • Have durable protection that lasts at least 1 year
  • Be suitable for all age groups.

Leroux-Rouels and colleagues have published on their recent research into the search for a universal influenza A vaccine (Lancet Infect Dis.  2023: S1473-3099(23)00351-1). Unlike current quadrivalent influenza vaccines that elicit antibody responses against the virus’ surface proteins and antigens (hemagglutinin and neuraminidase), the influenza A vaccine candidate OVX836 is a recombinant vaccine that targets the nucleoprotein, a highly conserved internal antigen hence much less likely to mutate. An industry-sponsored phase 2a trial evaluated the maximum tolerated dose in 137 healthy adults (18-55 years). Subjects were randomised to receive the drug (180 µg, 300 µg, or 480 µg doses) or placebo as a single intramuscular injection.

Results were promising

  • There was a favourable safety profile up to 480 µg
  • Good safety profile at all doses with mild local and systemic reactogenicity
  • Cell-mediated response was demonstrated between baseline and at 7 days (as measured by nucleoprotein-specific interferon-gamma)
  • Dose-dependent and polyfunctional nucleoprotein-specific CD4 T-cell responses were observed, and CD8 T-cell responses were elicited at 300 μg and 480 μg

The results of this study paves the way for extension studies, some currently underway in Australia

October 2023 - Is pre-operative screening for MRSA in joint arthroplasty patients effective?

The Therapeutic Guidelines: Antibiotics recommends pre-operative screening for MSSA and MRSA carriage, and decolonisation if detected, in patients undergoing arthroplasty and cardiothoracic procedures. It recommends swabs from more than 1 site (e.g., nose and groin) to improve detection. It recommends decolonisation with mupirocin 2% nasal ointment each nostril daily for 5 days +/- showering with antiseptic wash (chlorhexidine 2% or daily for 5-days OR bathing with a solution of diluted household bleach (60mL) daily for 5-days. It is recommended that the regimen is commenced at a minimum before the procedure but can be completed in the post-operative period.

Therapeutic Guidelines: Antibiotics recommendations are aligned with WHO recommendations apart from WHO recommending that 5-day decolonisation be completed pre-operatively, and performed once again on the day of the operation.

In recommending screening and decolonisation for MRSA and MSSA pre-arthroplasty in 2016, the WHO undertook a literature review used expert consensus. A summary of the evidence was considered from six randomised controlled trials including 2,385 patients comparing mupirocin +/- chlorhexidine body wash to placebo; the panel strongly recommended this for cardiothoracic and orthopaedic patients undergoing surgery on the basis of moderate quality of evidence. 

Suratwala et al. (J Hosp Infect. 2023; 138:27-33) have published on their experience of implementing pre-admission nasal MRSA screening to prevent SSI, and an evaluation of the cost-effectiveness and clinical utility at a US hospital.  They undertook a retrospective cohort study between 2005 to 2016, with the policy to screen implemented in 2011.

They found that the no-screening group had four MRSA infections in 6088 patients over a seven-year period, whereas the screening group had two in 5177 patients over five years. The cost of postoperative MRSA joint infection treatment was US$40,919.13 per patient, whereas annual nasal screening was US$103,999.97, adjusted to present day. The costs of nasal screening were related to lab costs (they used a PCR test to screen) and nurse practitioner time to perform the test, discuss results with patient and provide additional consultation for those who were colonised. They found that there was no statistically significant difference in rates of post-operative MRSA infections (0.066 infections versus 0.039 per 100 patients) before and after introduction of screening. They also noted that screening yielded positive results for 3.52 per 100 patients. 

The researchers concluded that implementation of screening and decolonisation pre-arthroplasty generated a substantial increase in annual hospital expenses and post-operative MRSA infection rates were far below the rate required to meet the screening costs. 

It should be noted that the researchers calculated total hospital costs due to MRSA post operative infections and did not include MSSA, a much more common post-operative infection. While the PCR screening test also identified patients colonised with MSSA, these patients were not offered decolonisation.

This study is of interest in exploring the considerations in justifying a screening program for S. aureus pre-arthroplasty, however, fails to consider MSSA infection outcomes. The case that has been put forward is whether universal screening is justified or whether it is possible to target screening to high-risk patients. There are no rigorous approaches to Identify patients colonised with S. aureus, while there is more literature on predictive risk factors for MRSA colonisation. When considering the implications of this study on screening policy, it is worth considering that there is already reasonable quality of evidence to justify pre-operative screening for patients prior to arthroplasty, and that post-operative infections could result in poor clinical outcomes and patient experience. 


August 2023 - The changing epidemiology of COVID-19

Assessing the incubation period of COVID-19 throughout emergences of variants of concern helps to establish duration of quarantine, informs contact tracing and surveillance approaches, and epidemic modelling. A previous meta-analysis updated in January 2021 estimated the mean incubation period was 6.38 days. A nationwide case-control study from France (Galmiche S et al. Lancet Microbe. 2023; 4(6):E409-E417) reports on determinants of the COVID-19 incubation period, including variants of concern, individual factors, and circumstances of infection. Symptomatic adults with confirmed COVID-19 on PCR testing from October 2020 to February 2022 were studied and incubation period defined as the number of days from contact with the index case to symptom onset.

Of 20, 413 participants

  • Mean incubation period varied across historical strain and variants
    • 4·61 days (95% CI 4·56–4·66) for the historical strain
    • 4·96 days (95% CI 4·90–5·02) for alpha (B.1.1.7)
    • 5·18 days (95%CI 4·93–5·43) for beta (B.1.351) and gamma (P.1)
    • 4·43 days (95% CI 4·36–4·49) for delta (B.1.617.2)
    • 3·61 days (95% CI 3·55–3·68) for omicron (B.1.1.529)
  • The incubation period was notably shorter with the omicron variant as well as in younger participants and in settings of high viral inoculum (e.g. symptomatic index, no mask worn)

These findings have potentially important implications for contact tracing strategies, surveillance definitions and infectious diseases modelling.

August 2023 - Surveillance of nosocomial COVID-19 in Norway

The Norwegian Institute of Public Health (NIPH) and the Norwegian Directorate of Health wished to establish a national surveillance system for healthcare-associated COVID-19.  The design of the system is described in this paper by Skagseth et al. (Euro Surveill. 2023; 28(12): 220493). Important characteristics of the system included:

  • Moving from manual data collection by clinical staff to greater reliance on electronic systems
  • New automated and semi-automated techniques such as data mining of patient records
  • Use of existing data on hospital admissions, vaccination status and their notifiable disease database. 

In setting up this system, they identified that there is no established definition for the parameters that define a nosocomial COVID-19 infection for surveillance purposes, and several different definitions have been used. It was identified that small variations in definitions greatly impacted the number of infections.

Cases were defined as people who had a positive PCR test during their hospital stay or within 7 days after discharge. Hospital stays that were 1 day or less apart were combined as a single admission.

Nosocomial infections were assigned to four categories based on the time interval between admission, discharge and positive test:

  • Community-acquired infection (CAI)
  • Indeterminate
  • Probable, or
  • Definite healthcare-associated infection (HAI).

The day of admission was counted as day 0. The following definitions were applied to classify HAI:

  • All cases with a positive PCR test within 1-day post-admission were classified as CAI
  • A ‘definite HAI’ defined cases who had a positive test while hospitalised if the sample was taken 14 days or more after admission and those who tested positive on their first day post-discharge if they had been admitted to hospital 14 or more days before
  • A ‘probable HAIdefined cases who (i) had a positive test 7–13 days post-admission, or (ii) tested positive on their first day post-discharge if they had been admitted to hospital 8–13 days before and (iii) those who tested positive 9 or more days post-admission on day 2 post-discharge.
  • An ‘indeterminate HAI’ included all those who either had (i) a positive test 2–6 days after admission and were still in the hospital, (ii) a positive test 1 day after discharge and 3–7 days after admission, (iii) a positive test 2 days after discharge and 4–8 days after admission or (iv) a positive test 3–7 days after discharge.

Of 1,433,687 patient stays from March 2020 to March 2022, 15% were 7 days or more. The incidence of HAI COVID-19 varied over the course of the pandemic; few nosocomial infections were identified earlier in the pandemic with higher numbers identified with delta variant (from 2021week 26) further rising with the omicron variant (from 2021 week 52).  Overall, 0.044% of cases were probable or definite HAI.  Sensitivity analysis with a range of definitions for nosocomial COVID-19 (e.g. definite HAI 8-15 days) demonstrated that these numbers can be influenced by the definition of HAI.

The authors concluded that while  their current definitions based on incubation time and hospital admission appeared to work well for conservative estimates of nosocomial infection rates, it would be important to adjust these to reflect changes in incubation periods of different variants.


June 2023 - Using Human Factor Engineering approach to understand and design HCW Hand Hygiene interventions

Vaughan-Malloy et al (AJIC 2023 May) have published a study where they developed an electronic survey using Human Factor Engineering (HFE) approach.  The HFE approach was selected because it has been widely used in healthcare settings and demonstrated impact at individual, group and system levels. Developed from the Systems Engineering Initiative for Patient Safety 2.0 model, the survey questions explored 6 domains, resulting in a 24-item electronic questionnaire.  Domains included technology and tools, person, organization, tasks, environment, and care processes.

 

The electronic survey was offered to HCW in a quaternary care paediatric hospital, and data captured via REDCap. There was a 31% response rate. Among 61 respondents, 70% perceived HH as “essential” to patient safety.  Results highlighted differences in perceived facilitators and barriers to high reliability in hand hygiene between clinicians in surgery/anesthesia versus medical specialties and identified different approaches that may be effective in improving hand hygiene compliance. 

 

It is often said that understanding the problem is half the battle, and solutions that are tailored to address identified barriers are more likely to be successful. This study offers a survey tool developed using HFE, that can support healthcare organisations to understand and design targeted interventions to increase HCW hand hygiene compliance.

June 2023 - The presence of skin bacteria in the sternal wound and contamination of implantation materials during cardiac surgery

Sandström et al have published a study (J Hosp Inf 2023 Mar 31) investigating the presence of skin bacteria in the cardiac surgery sternal wounds and to evaluate their possible ability to contaminate surgical materials.

The study examined 50 patients that underwent coronary artery bypass graft surgery and/or valve replacement surgery; cultures were collected from skin and subcutaneous tissue at two time points during surgery, and from pieces of vascular graft and felt pressed against subcutaneous tissue. Interestingly, routine surgical antibiotic prophylaxis in this Swedish hospital for CABG surgery was cloxacillin (similar in spectrum of activity to flucloxacillin) and benzylpenicillin (active against C. acnes).

Researchers found that cultures from skin had bacterial growth in 48% of patients at surgery start and in 78% after two hours, and cultures from subcutaneous tissue were positive in 72% and 76% of patients, respectively. The most common isolates were C. acnes and S. epidermidis. Cultures from surgical materials (vascular graft and polyurethane felt used to reinforce suture lines) were positive in 80-88%.

These findings help provide biological plausibility to a long-standing question: how can post-operative infections (sternal wound or graft infections) emerge many years after primary surgery? The results of this study show that a surgical wound is not sterile and likely contaminated with the patient’s own skin bacteria (previously known from other studies) and that surgical materials are also likely to be contaminated by the same bacteria (new finding).  The researchers propose that as both S. epidermidis and C. acnes can produce biofilm, these bacteria are able to adhere to and persist on foreign materials that have been implanted, even if clinical infection does not occur in the early post-operative period.



April 2023 - Does Selective Decontamination of the Digestive Tract improve outcomes in mechanically ventilated ICU patients?


Since the first studies were published decades ago, selective decontamination of the digestive tract (SDD) remains one of the most controversial topics in the treatment of critically ill patients. The theory is that reducing incidence of ICU-infections by eradicating and preventing colonisation of the digestive tract with antimicrobial agents that selectively spare anaerobic flora improves patient outcomes such as mortality.  Uncertainty remains on whether such an intervention:

    • Unequivocally benefits patients
    • Contributes to widespread risk of antibiotic resistance, and if so, is this sufficient to outweigh potential individual patient benefits

The SuDDICU study published in JAMA late last year looked at this question:

Among critically ill mechanically ventilated patients (those expected to require >48 hours of mechanical ventilation), what is the effects of selective decontamination of the digestive tract (SDD) on hospital mortality (all-cause mortality, within 90-days of enrolment)?
Secondary outcome measures were
(1) clinical - ICU mortality, days alive and free of mechanical ventilation, ICU and admission at 90-days
(2) microbiology - positive blood cultures, incidence of new CDI, incidence of resistant organisms from clinical cultures, antibiotics received over 28-days. 

This question was examined in an Australian cluster randomised trial (patients randomised to SDD or standard care), with a cross over design in participating ICUs (12 months of intervention 1, 3-month interperiod gap, 12 months intervention 2). 

The intervention was:

  1. 6-hourly topical buccal and oropharyngeal application of an antimicrobial oral paste of colistin, tobramycin, nystatin AND
  2. 6-hourly gastric suspension of similar antimicrobials AND
  3. 4-day course of IV antibiotic with activity against Gram-negative bacteria (e.g. ceftriaxone, ciprofloxacin).

An ecological study was also undertaken to examine microbiology secondary outcomes, where all patients admitted to ICU were assessed for a 1 week for outcomes at five time periods (pre-trial, intervention 1, interperiod, intervention 2, post-trial).

 

SUDDICU included 5,982 patients from 19 Australian ICUs. Primary outcome results were:

    • In-hospital mortality within 90-days - 753/2791 (27.0%) in intervention group, 928/3191 (29.1%) in control group, where differences were not statistically significant
      • Mean difference -1.7%, 95%CI, -4.8 to 1.3%
      • OR 0.91, 95% CI, 0.82-1.02, p=0.12
    • Of microbiological secondary outcomes
      • There was no statistically significant difference between groups for new CDI and antibiotic use (DDD over 28 days) between groups
      • There was a statistically significant difference in new antibiotic-resistant organism found and positive blood cultures (both favouring intervention group)

The authors conclude that while SDD did not statistically significantly reduce in-hospital mortality in this study, the confidence interval around the estimate suggests a clinically important benefit. It should also be noted that eligible patients were those expected to require >48 hours of mechanical ventilation, which is a minority (around 10%) of Australian ICU patients requiring mechanical ventilation. They also conclude that as there was a low rate of antimicrobial resistance and a relatively short period of observation in the participating ICUs, the effect of SDD in environments of higher antimicrobial resistance remains unknown.

SUDICCU’s results were included in a new meta-analysis by Hammond et al (JAMA 2022;328 919):1922-1934) also published in the same journal edition. 32 randomized trials with 24,389 patients of selective decontamination published between 1987 to 2022, pooled relative risk for in-hospital mortality was lower with decontamination than usual care (0.91 (95% credible interval [CrI], 0.82-0.99; I2 = 33.9%; moderate certainty). The beneficial association of SDD was evident in trials with an intravenous agent (RR, 0.84 [95% CrI, 0.74-0.94]), but not in trials without an intravenous agent (RR, 1.01 [95% CrI, 0.91-1.11]) (P value for the interaction between subgroups = .02). SDD was associated with reduced risk of ventilator-associated pneumonia (RR, 0.44 [95% CrI, 0.36-0.54]) and ICU-acquired bacteremia (RR, 0.68 [95% CrI, 0.57-0.81]).

Hammond et al conclude that use of SDD in mechanically ventilated ICU patients reduces hospital mortality; and that this reduction is evident in trials with an IV agent as a component.  However, there is lower certainty as to how this is achieved. They conclude that there was no evidence that SDD was associated with an increase in incidence of resistant organisms, however describe the evidence around this as very uncertain.

While it is proposed that benefit of SDD interventions that include IV antibiotic(s) is potentially conferred through preventing VAP or HA-bloodstream infection, it is also possible that benefit is also potentially through use of these IV antibiotics as pre-emptive therapy (in patients not yet diagnosed with bacterial infection). SUDDICU and this meta-analysis was recently discussed in a forum hosted by ASID; a planned recording will be made available and disseminated via ASID.  There was panel and participant discussion around mortality benefit to patients (yes/no/maybe) and whether this intervention contributes to increased risk of antibiotic resistance for implementing ICUs and hospitals. Although not in the SUDDICU protocol, active surveillance for MROs would be important to consider if implementing to provide further assurance on the safety of SDD and impact on AMR in our ICUs and hospitals.

April 2023 - COVID-19 Staff surveillance testing reduces resident cases related to COVID-19 outbreaks in aged care facilities 


McGarry et al (NEJM 2023;338:1101-10) have published research showing that in current COVID-19 settings, COVID-19 staff surveillance in skilled nursing facilities in the US (comparable to Australian residential aged care facilities) reduces COVID-19 cases and potential outbreaks. 

Examining data from 2020 to 2022, they performed a retrospective cohort study for COVID-19 in staff of 13,424 facilities, assessing staff testing volumes (with PCRs, and then RATS when they became available) with COVID-19 cases and deaths among residents during potential outbreaks (defined as 1 new case after 2 weeks with no cases). They reported differences in outcomes between high-testing and low-testing facilities.

The study found

    • On average, all facilities performed 1.1 surveillance tests per staff member
      • With high-testing facilities preforming an additional 0.6 tests/staff-week compared to average
      • With low-testing facilities performing 0.5 fewer tests/staff week compared to average
    • High-testing facilities had 15% more staff COVID-19 cases than low-testing facilities
    • During the omicron period (Nov 2032 to March 2022)
      • high-testing facilities compared to low-testing facilities had 1038.2 versus 1092.9 resident cases /100 potential outbreaks (adjusted difference -54.7;95%CI, -102.2 to -7.2)
      • no difference in COVID-19 related resident deaths (however analysis showed there was a significant difference in the pre-vaccination period, before January 17, 2021)

Study limitations included

    • Potential confounding as a reason for differences between COVID-19 resident related case and death outcomes. High-testing facilities were more likely to be non-profit, have a five-star quality score, different resident demographic, and have smaller staff sizes
    • An assumption is that pre-symptomatic staff members are probably the primary mechanism for introduction of COVID-19 into a facility and transmission to residents. The authors note that visitors were largely excluded from these facilities before 2021.

Despite study limitations, this study supports conclusions of modelling studies suggesting that an effective surveillance system, with staff testing at least twice weekly in high-risk settings, can reduce introduction of COVID-19 into a facility.   Importantly, this study suggests that at a time where residents are vaccinated, this surveillance approach remains effective in achieving clinically meaningful reductions in COVID-19 cases and potential outbreaks.



February 2023 - Outcomes from a quality improvement initiative to reduce colorectal SSI in England

Clayphan et al (J Hosp Inf 2022;130-137) describe the outcomes of a study to establish reliable SSI measurement after elective colorectal surgery using 30-day patient-reported outcome measures (PROM), and to implement the four-point care bundle to reduce the 30-day SSI rate in seven hospitals by 50% from 2019-2020.


Public Health England (PHE) requires mandatory SSI reporting following orthopaedic surgery, but not following gastrointestinal surgery. There is no benchmark for SSIs in PHE hospitals after elective colorectal surgery, and most hospitals do not know their SSI rates. SSIs are captured during inpatient stay or readmission data.

The WHO SSI bundle, part of the surgical safety checklist used in the NHS, consists of four key interventions shown to reduce infection independently: antibiotics within 1h of surgery, normothermia, blood glucose control in diabetics, and appropriate hair removal. Despite high compliance with this, one PHE hospital further halved their SSI rate using an additional four-point care bundle. This is the care bundle used in this study. It is composed of 2% chlorhexidine skin preparation, redosing of antibiotic for long procedures (4h or longer), use of a dual ring wound protector, and antibacterial (Triclosan-coated) sutures for abdominal wall muscle and skin closure.

To collect superficial SSI using 30-day patient-reported SSI rate, a PHE-validated questionnaire was used to monitor SSIs after surgery as part of patient-reported outcome measures. This questionnaire is designed to detect superficial wound infections based on patient-assessed appearance and management of the wound, according to the three criteria: Criterion 1 – discharge pus AND antibiotics prescribed; Criterion 2 – clinical signs (at least two of: pain, heat, redness, swelling) AND dehiscence; or Criterion 3 – clinical signs AND antibiotics prescribed.

The study authors reported an overall 50% reduction in SSI rate from 18% (1447 patients) to 9.5% (1247 patients) was achieved after elective colorectal surgery, with 6 out of 7 hospitals achieving SSI reduction. The average questionnaire response rate was 81%, and average compliance was 92%, 96%, 79% and 85% for each element of the bundle.

Some of the challenges described in implementation include
  • Data collection for bundle compliance was challenging, meaning that some bundle elements were not recorded as compliant when they had been delivered.
  • Data collection from PROMS using paper or telephone questionnaires is costly in manpower. After the trial, one hospital trialled electronic PROMS, which involves sending a text or e-mail form of the questionnaire to patients and reduction in manpower requirements, and described reduced response.
  • Baseline use of chlorhexidine was already high.
  • Antimicrobial sutures and antibiotic redosing were completely new interventions in almost all hospitals, it is likely that these were the main contributors to the reduction in SSI rates.
  • There was less compliance uptake with use of wound protectors (felt to be related to surgeons’ historical concerns about this approach) and it was felt to be unlikely that this bundle element contributed greatly to the reduction in SSI rates.
In surveillance, SSIs are usually identified during patient admission or readmission, hence superficial SSI may be under-detected. The use of PROM to contribute to SSI surveillance is novel and of interest. It has potential value in screening for patients with infection outcomes post-procedure not identified during their hospital stay or readmission. The definitions for superficial SSI used by the PHE questionnaire in two of the three criteria require the patient to have been started on antibiotics, however does not exclude patients that might meet the clinical criterion for cellulitis or stitch abscess. This is different to VICNISS definitions and may partially explain the higher rates in colorectal SSI reported in this study compared to VICNISS participating hospitals who have reported 5-year aggregate SSI rates of 5.2% (9,269 procedures), with 58.0% reported as superficial SSI (rate 3.1% per 100 procedures). Victorian surveillance periods are to 30-days.


February 2023 -  Effectiveness of patient and staff cohorting to end a vanA VRE outbreak in a Japanese hospital.

Kakimoto et al (J Hosp Inf 2023;S0195-6701(23)00006-3) quantified the risks of acquiring vancomycin-resistant Enterococcus faecium (VREfm) at a hospital during an outbreak based on contact characteristics to better understand the effectiveness of cohorting.

Detection of VRE in hospitals had been rare in Japan. This study was undertaken in the setting of a hospital outbreak of VREfm harbouring vanA in 2018, in which most patients with VREfm were found through regular VRE screening culture of stool or rectal samples.

Among 272 inpatients (4038 patient-days), 43 patients acquired VREfm with the same or similar pulsotype. Incidence rates were 8.45 per 1000 patient-days when susceptible inpatients were in the same ward with infectors but cared for by a different care team, 16.96 when cared for by the nurses who cared for infectors (IRR: 2.01, 95% CI, 0.62-10.28), and 52.91 when sharing the room with infectors (IRR: 6.26, 1.61-35.40).

They conclude that enhanced surveillance and cohorting played an important role to ending the outbreak, in addition to enhanced measures around hand hygiene compliance, environmental cleaning and antimicrobial stewardship. Compared to being in a different room and not being cared for by VREfm patient-care nurses, the risk of VREfm acquisition could be six times higher for patients who are in the same room with VREfm patients and could be double for patients cared for by VREfm patient-care nurses.



December 2022 - Early return-to-work program for contagious health care workers

Here Dr Lyn-li Lim takes a look at an article on an early return-to-work strategy for contagious COVID -19 staff (Wagester S et al AJIC 2022 doi: 10.1016/j.ajic.2022.11.006). This study was undertaken at a 40-hospital integrated healthcare system providing care throughout Pennsylvania.  It was undertaken as an Ethics-approved Quality Improvement project.

To investigate an alternative strategy to reduce HCW workforce shortages imposed by requirement for staff to not return for a minimum 7-day post-infection (the updated CDC guidelines as of December 2021), the program offered voluntary self-enrolment of HCW who had tested positive for COVID-19, had resolution of respiratory symptoms, were not immunocompromised, and felt well enough to return to work the opportunity to

  • Undertake and self-report COVID-19 RAT at Day 5
  • If RAT result was negative, opportunity for early return to work (RTW) on Day 6. If result positive, HCW did not return to work for 10 days (as was the organisational policy)

The primary outcomes included number of HCW eligible for RTW and number of days saved from missed work (calculated based on 10-days off work). The secondary outcomes included transmission after early RTW (by examining contact tracing logs to identify if any HCW participating in early RTW program was subsequently part of a COVID-19 transmission cluster.

They reported that over a 3-month period in early 2022, of 1,023 HCW enrolled in program, 33.6% self-reported negative RAT results at Day 5 and were hence eligible for early RTW. Hence they calculated a total of 714 days saved from missed work (assuming 10 days off work). No transmission events were observed as originating from early RTW participants.

The authors cautiously recommend that in the setting of workforce shortages, their study demonstrates the feasibility and minimum risk of such an approach, noting that risk was likely also mitigated by universal masking policy in place at the time.

December 2022 - Strategies to improve the implementation of infection control link nurse programs in hospitals

Dekker and colleagues (J of Hospital Infection 128 (2022) 54-63) conducted a study that looked at challenges in implementing infection control link programs and strategies to overcome these. Link nurses are described as nurses that are ward-based, supported by hospital Infection Prevention and Control teams, to observe, inform and instruct their ward-based colleagues on infection prevention practices.

To identify the challenges, researchers used Delphi technique to ask a group of experts on their opinions. The outcomes of Delphi panels do not provide right or wrong answers, but look at achieving consensus and the authors suggest that their findings are best used to ensure there is planning to identify and manage potential barriers when implementing or reviewing use of link nurses as part of Infection Prevention and Control approaches.

Potential barriers identified included:

  1. Infection control has no priority at the hospital level
  2. The role of the link nurse is not defined
  3. Link nurses are not accepted by medical staff
  4. Link nurse programs are initiated, developed and implemented solely by infection control practitioners
  5. Responsibility to educate the link nurse lies with infection control practitioners
  6. Connecting link nurses to exchange experience and best practice is challenging
  7. Link nurse programs are not evaluated

The most prominent strategy discussed is to identify and prepare the champion.  Qualities that are important in champions are sustained and enthusiastic advocacy for the program, convincing others that the intervention is important and leading by example.   Strategies for preparing and supporting the champion include education, establishing a learning collaborative and, interestingly, providing opportunities to develop their facilitator skills (described as interpersonal, communication and leadership skills).




October 2022 - Hand hygiene compliance by direct observation in doctors and nurses

Direct observation using tools such as National Hand Hygiene Initiative hand hygiene audits is the current gold standard method to assess hand hygiene compliance. 

In this systematic review and meta-analysis, Bredin et al (J Hosp Inf Sept 8 2022) examines the literature for differences in compliance between physicians and nurses and to analyse if compliance estimates varied  between covert and overt approaches. They included 105 studies in their review which was limited to studies published in English and from high-income countries. They found:

      • Higher pooled compliance rate for nurses (52%, 95% CI 47 to 57%) compared to physicians (45%, 95% CI 40 to 49%)
      • However there was considerable heterogeneity and majority of studies were at moderate of high risk of bias
      • Random-effects meta-analyses of low risk of bias studies (9 studies) suggests nurses have higher compliance over physicians for both overt (7 studies) and covert (2 studies) observation.
      • Four studies gave a breakdown of physician and nurse compliance separately by WHO five moments for hand hygiene. Nurses recorded higher compliance than physicians in 3 of 4 studies for Moments 1 and 2, and all studies for Moments 4 and 5.  Physicians recorded higher compliance in 3 studies for Moment 3.

Donna Taylor, VICNISS ICP, has taken a look at Victorian hospital hand hygiene data reported over the last two years. These are some common findings

      • Compliance in nursing staff is consistently higher than medical staff
          • Nurses’ compliance for moments 1, 2, 4 & 5 greater than medical staff
          • Moment 3 highest level of compliance (consistently) for medical staff but not always above nurses (3 out 6) over the last 2 years.
      • Nurses overall hand hygiene compliance has decreased slightly throughout the pandemic; ranging from 84.42% to 86.2% over the past two financial years compared with 88.1% to 89.5% during the previous two financial years.
      • Compliance in medical staff has somewhat improved throughout the pandemic; ranging from 78.8% to 80.2% over the past two financial years compared with 75.6% to 76.8% during the previous two financial years.
      • The number of missed moments involving gloves has reduced throughout the pandemic; missed moments when doffing gloves 5.8%, missed moments donning gloves 11.3% and missed moments from all healthcare workers involving gloves 10.8% compared with previous two years 7.0%, 13.0% and 12.1% respectively.
      • Victorian small hospitals hand hygiene compliance is slightly higher than large hospitals 88.64% and 85.82% respectively, over the past two financial years.

Donna’s observations are that the differences in patterns of compliance between nurses and doctors may be related to task type and familiarity. Generally, nurses provide most of the direct patient care, with a high level of interaction occurring between nurses and patients throughout each shift (moments 1, 2, 4 & 5) which again leads to familiarity with tasks and hand hygiene moments. 

Medical staff perform procedures (e.g. line insertion, taking blood, aspiration) which likely results in familiarity with tasks (moment 2 hand hygiene, gloves on, moment 3 gloves off, hand hygiene). 

Literature has shown that improvement in hand hygiene compliance can be achieved by focusing on ensuring hand hygiene product availability and placement, targeting education around missed moments, in particular donning gloves, and identifying opportunities for face-to-face feedback and education.

October 2022 - Rectal swab screening for MDR bacteria

Healthcare facilities are required to undertake surveillance for MDR bacteria in response to identified cases, outbreak settings, or identified changes in local transmission rates.

For Enterobacterales or Entercoccus spp., the reservoir is the gastro-intestinal tract. In the CPE guideline for Victorian health services, sample collection for carbapenemase-producing Enterobacterales  should be with a faecal specimen where possible. If obtaining a faecal specimen is not possible, then a rectal swab (with evidence of faecal matter on the swab) plus an inguinal swab should be taken. A rectal swab alone is the least preferred screening specimen.

This paper from Le Guen et al (J Hosp Inf Sept 13 2022) explains the potential risk of using rectal swabs alone to clear patients from colonisation. It suggests that tests of sample quality can significantly contribute to reliability of test result.   They examined just over 1,000 rectal swabs sent to a microbiology lab for MDR screening (organisms included CPE, ESBL-Enterobacterales).  They found that detection of the MDR organism matched the amount of faecal matter on the swab.  They objectively proved it by classifying samples received according to appearance in a liquid transport medium (turbidity scale range e.g. very tinted, cloudy, slightly cloudy) to bacterial loads.  They showed that samples that were classified as slightly cloudy and limpid swabs (the two least turbid classifications) comprised one-fifth of the rectal swabs received, which resulted in unpredictable bacterial loads. 

This study shows that the appearance of a rectal swab is correlated with bacterial load.  However, this test of sample quality is not commonly performed by clinicians submitting the sample or by the lab processing the sample.  They postulated that a negative screening test result in these samples could lead to the incorrect conclusion that the person is not colonised with the organism.  In their study this occurred in up to one-in-five samples. 

Due to lack of samples for VRE, their findings need to be confirmed for VRE, but it is likely that the inferior performance of rectal swabs over faecal samples would hold.



August 2022 - Intraoperative transmission of bacteria – how does it occur?

SSIs are detrimental to patient outcomes, resulting in poorer clinical outcomes, longer hospital stays and higher readmission rates.  Victorian hospital-acquired infection reports consistently show S. aureus as the leading pathogen causing surgical site infections (SSI). This paper from Loftus et al (AJIC 2022) explores the transmission dynamics of S. aureus in the operating room environment. 

In this study, 274 paired operations were observed.  Microbiological sampling was undertaken of the following

    • Provider’s hands (providers of anaesthetics) before induction and after patient care
    • Patient’s nasopharynx and axilla after induction
    • Environmental sampling of dials of the anaesthetic machine before case 1 (after decontamination), end of case 1 and end of case 2
The samples were sent for culture and sensitivity as well as clonal sequencing (using multi-locus sequence typing).

Transmission dynamics were organised to the following groups according to definitions detailed in the study

    • Provider origin within the case
    • Provider origin between case 1 and 2
    • Environmental origin within the case
    • Environmental origin between case 1and 2
    • Patient origin within case
    • Patient origin between case 1 and 2

The results of this study identified 58 clonal S. aureus transmission events between the 274 paired cases. As well, they demonstrated that clonal transmission was associated with higher multidrug resistance. Provider hands were a frequent reservoir of origin, between-case a common mode of transmission, and patient skin and provider hands frequent transmission locations. While only just published, this study was of procedures in US hospitals in 2009 to 2010. Victorian SSI rates have improved over the last decade. This study serves as an important reminder on the importance of provider hand hygiene, environmental cleaning and patient decolonisation on minimising SSI risk.



August 2022 - First UK experience implementing C.auris RT PCR surveillance in hospital setting – does it improve clinical risk reduction?

C. auris is an uncommon, multidrug resistant Candida species that has been associated with outbreaks of invasive infections in healthcare facilities internationally. Australia’s national alert system for Critical Antimicrobial Resistances (CARAlert) includes C. auris as organism of interest. In 2021, one case was reported from Victoria

Taori and colleagues report on first UK experience implementing C. auris RT-PCR surveillance in a hospital setting (J Hosp Inf June 2022). After a major outbreak in 2016, an in-house PCR was developed to support a PCR-based surveillance program in high-risk areas.  They describe the outcomes from January 2018 to March 2019.  21 C. auris colonised patients were identified using urine catheter specimens and nose, throat, axilla and groin swabs. They describe median turnaround that fell from 5.8 days to 24hours, enabling rapid infection control precautions.  They noted that a chromogenic agar has now also become available for rapid screening and a direct comparison of performance against this would be of interest.




June 2022 - New updated guidelines for central line-associated bloodstream infection (CLABSI) prevention in hospitals

Taking measures to prevent health-care–associated infections (HAIs), including central line-associated bloodstream infections (CLABSIs), is crucial in acute-care hospital settings.

In VICNISS’ April literature review, we presented US Agency for Healthcare Research and Quality’s (https://www.ahrq.gov/hai/tools/clabsi-cauti-icu/index.html) updated resources for preventing CLABSI in ICUs. In this month’s review, we present newly updated CLABSI prevention guidelines, Strategies to Prevent Central Line-Associated Bloodstream Infections in Acute-Care Hospitals, a collaborative work between peak US expert groups SHEA, IDSA, ICHE (Buetti et al. Infect Control Hosp Epidemiol. Published online April 19, 2022).

Updates to recommended best practices for hospitals (deemed “essential practices”) include:

      • "The subclavian site is preferred to reduce infectious complications when the catheter is placed in the intensive-care unit.” Previously it was recommended avoiding the femoral vein for access. This is still best practice but was replaced by the positive recommendation of the subclavian site.
      • “Use ultrasound guidance for catheter insertion.” There is higher quality evidence than was available previously, but this procedure could potentially jeopardize the ability to ensure sterile technique.
      • “Use chlorhexidine-containing dressings for CVCs in patients over 2 months of age,” was previously a special approach but is now an essential practice.
      • “Routine replacement of administration sets not used for blood, blood products, or lipid formulations can be performed at intervals of up to 7 days.” The interval was up to 4 days in previous guidelines.

The guidelines recommend avoiding using antimicrobial prophylaxis for short-term or tunneled catheter insertion or while catheters are in situ, and routinely replacing CVCs or arterial catheters. Some issues remain unresolved, such as the use of needleless connectors, sutureless securement, and CLABSI risk associated with non-antimicrobial transparent dressings.

June 2022 - New build hospital design features that optimise pandemic response

Royal Adelaide opened in early 2020 and acting as a receiving hospital for hospitalised COVID-19 patients. Elke Kropf and Kathryn Zeitz recently published work (Aust Health Rev, 2022) describing key design elements of this 800-bed new build with disaster response infrastructure design features.

Pandemic design features included

      • 100% single rooms – to provide flexibility, secure patient privacy, more family/carer inclusivity, and reduce patient movements as more treatments could occur in their room.
      • Reduced number of generic spaces for treatment or procedure rooms
      • PPE stations built into external corridor prior to access into each room
      • Standardised layout of rooms to aid infection prevention
      • Design incorporated 35 negative pressure rooms, 3 full quarantine rooms spread across ED, inpatient, ICU and recovery bays
      • Security card readers activated to only allow restricted staff access to each zone
      • Heating, ventilation and air conditioning (HVAC) design features included pandemic zones, changes to HVAC in oandemic mode include no air recycling options

Mapping use of clinical spaces in pandemic described

      • Designing use of clinical areas to support clinical service, that can be scaled up and down according to need
      • Separation of an infectious patient pathway
      • Consideration of patient journeys through hospital, staff movements and separation of public and staff/patient paths
      • Creation of pod spaces in clinical areas such as ED


April 2022 - Impact of COVID-19 on healthcare-associated Infections

COVID-19 pandemic has placed extraordinary demands on healthcare systems, in Australia and internationally. These demands could have the potential to either increase or decrease risks for HAIs. 

Baker and colleagues (Clin Infect Dis, Aug 9 2021) evaluated the association between COVID-19 surges between January 2020 and September 2020 and HAI rates in 148 US hospitals. CLABSI, CAUTI, MRSA bacteraemia and CDI reported to CDC’s National Health Safety Network was analysed. This evaluation found:

  • Certain HAI increased as COVID-19 burden increased; with more cases for CLABSI 60% 95% CI, 23-108%), CAUTI 43% (95%CI, 8-90%) and MRSA bacteraemia 44% (95% CI, 10-88%) than when compared to historical estimates had there been no COVID-19 cases
  • HA-CDI was not significantly associated with COVID-19 burden
  • Rates of hospital-onset bloodstream infections and MRSA were each significantly associated with COVID-19 surges

This analysis supports the hypothesis that certain HAI rates are adversely affected by the pandemic response and highlights the importance of identifying strategies to ensure sustainability of routine infection prevention programs even in periods of public health crisis that require diversion of healthcare resources. 

April 2022 -  Newly updated customisable, educational toolkit to help ICUs reduce rates of central line-associated bloodstream infection (CLABSI) and catheter-associated urinary tract infection (CAUTI)

In Australia, healthcare-associated infections (HAI) affect around 1 in 10 hospitalised patients and these infections are largely preventable. UTI is one of the most common HAI (behind SSI and pneumonia). CLABSI are associated with a significant increased risk of death.

The US Agency for Healthcare Research and Quality (https://www.ahrq.gov/hai/tools/clabsi-cauti-icu/index.html) has updated resources for preventing CLABSI and CAUTI in ICUs.  Resources are arranged in the following order:

  • Assess – how to understand current clinical and safety practices around CLABSI and CAUTI
  • Implement – guidance on implementation of activities around CLABSI and CAUTI prevention
  • Overcome - tips and considered approaches if stuck on a particular challenge and need support to find actionable solutions

There are resources on overcoming common challenges in making changes to patient safety culture. They include:

  • Information sheets (“Making It Work”)
  • Interviews with subject matter experts
  • Videos seeing teams live out some common challenges while a narrator highlights key points

While these resources are related to HAI in ICU, many of these resources are useful for other hospital settings.


February 2022 - 2022 HCW seasonal influenza vaccination campaigns

With the reopening of national and jurisdictional borders, it is expected that seasonal influenza will re-emerge and circulate in Australia.  Reports from the US and Europe report higher levels of circulating influenza than previous two seasons. The dominant circulating virus is Influenza A subtype H3.

The CDC reports that most A(H3N2) viruses identified so far this season are genetically closely related to the vaccine virus, with some antigenic differences as the virus has continued to evolve. To 22nd January 2022, there have been at least 2 million flu illnesses, 20,000 hospitalisations and 1,200 deaths from flu. Long-term care facilities undertake weekly influenza surveillance in residents; the percentage of facilities currently with at least one influenza positive test among their residents peaked at 1% in late January.

We saw the impact of COVID-19 on HCW vaccination uptake in 2021.  In aggregated data submitted to VICNISS, the proportion of vaccinated staff in Victorian public hospital and health services was 77.4% compared to 93.0% in 2020, and in public service residential aged care services (PSRACS) 88.1% compared to 98.9% in 2020. It is of note that influenza vaccination was mandated in aged care HCW in 2020 under public health orders. Proportions of HCWs with undeclared/unknown vaccination status increased four-fold in 2021 in both settings. There were no public health order mandates for Victorian HCW influenza vaccination in 2021. Planning for 2022 annual flu campaign is in progress.

In December 2021, ATAGI provided an update on seasonal influenza vaccines in 2021.It is anticipated a new report will be issued shortly for the clinical advice on the administration of seasonal influenza vaccines in 2022.  Of note in the published December update:

  • Influenza vaccinations must be recorded on the Australian Immunisation Register
  • Influenza vaccines can be co-administered with COVID-19 vaccines
  • Influenza activity may be atypical and clinicians should be alert to interseasonal influenza activity and the possibility of influenza in persons presenting with respiratory symptoms (who do not have COVID-19) including those who have returned from overseas

 The Australian Influenza Vaccine Committee (AIVC)  has recommended the composition of the influenza virus vaccines for 2022. 

Egg-based quadrivalent influenza vaccines:

  • an A/Victoria/2570/2019 (H1N1)pdm09-like virus;
  • an A/Darwin/9/2021 (H3N2)-like virus;
  • a B/Austria/1359417/2021-like (B/Victoria lineage) virus; and
  • a B/Phuket/3073/2013-like (B/Yamagata lineage) virus.

Cell- or recombinant-based quadrivalent influenza vaccines:

  • an A/Wisconsin/588/2019 (H1N1)pdm09-like virus;
  • an A/Darwin/6/2021 (H3N2)-like virus;
  • a B/Austria/1359417/2021 (B/Victoria lineage)-like virus; and
  • a B/Phuket/3073/2013 (B/Yamagata lineage)-like virus.

The AIVC recommendation for the composition of influenza vaccines for Australia in 2022 differs from the 2021 southern hemisphere and 2021/22 northern hemisphere recommendations with the inclusion of two new strains for the A (H3N2)-like and B Victoria lineage viruses. The recommendation made by AIVC aligns with the recommendation made by the World Health Organisation.

February 2022-Hospital infection control practitioners in COVID-19 pandemic – what competencies are important?

Cui and colleagues propose a new model to comprehensively evaluate the competency of ICPs in recognition of the new challenges put forward by pandemic COVID-19 on nosocomial infections. They adopted a mixed-methods approach (using literature review, key informant interviews, Delphi method to develop a measurement scale, then questionnaire of ICPs) to develop and evaluate a competency evaluation model.

This model recognises key elements in ICP roles with COVID-19 (Figure 1). It recognises that numerous nosocomial events during COVID-19 pandemic has introduced information technology elements to the ICP role, for example use of digital technology to control and prevent outbreaks and to disseminate information in a timely manner.

For those of you who are working tirelessly to support health services in your vital roles through the COVID-19 pandemic, we applaud you.



December 2021 - Monitoring the burden of CDI in Australian public hospitals to inform the development of appropriate measures to prevent and limit the spread of CDI in both the community and healthcare settings

The Australian Commission for Safety and Quality in Health Care has published a report on rates of Clostridioides difficile infection (CDI) in Australian public hospitals. Using patient administrative data, it is reported that between 2016 to 2018

  • The number of separations with a CDI diagnosis increased by 8.4%
  • Of 24,247 separations, 76.5% presented to hospital with CDI symptoms
  • 32.5% developed CDI symptoms during their hospital admission
  • The number of separations coded as COF1 non-principal CDI diagnoses (i.e. hospital-acquired CDI), however, decreased by 3.8.%
  • Patient administrative data methodology (using diagnostic coding and hospital-acquired complications data) was compared against laboratory or hospital-identified infection surveillance data (the gold standard) as a means of identifying prevalence of CDI in Australian public hospitals
    • The Tasmanian DoH study compared 194 CDI cases identified from hospital surveillance to 232 cases identified from coded patient data. There was an overall sensitivity of 71.4% with PPV of 74.9%.
    • A tertiary referral hospital study compared 540 cases from hospital surveillance to 586 cases from HACs data.  There was an overall sensitivity of 47% with PPV of 68%.
  • Data on hospital antimicrobial usage (from NAUSP) from 2016 to 2018 was compared to CDI rates
    • It was determined that NAUSP data will not be included in future CDI data reports as use of different denominators and heterogeneity in NAUSP for CDI reporting at sites result in findings that are not generalisable

Victorian public hospitals undertake surveillance as part of infection prevention and control activities. 
Aggregated results are published annually in VICNISS’ annual report.

Victorian public hospital HA-CDI rates, January 2011 to June 2021

Facilities reporting HA-CDI (denominator supplied) OBD Rate per 10,000 OBD Comments
Jan 2021 to Jun 2021 (n=92) 593 2,734,693 2.17 Continuous surveillance, mandatory reporting
Jul 2020 to Dec 2020 (n=91) 484 2,583,081 1.87 Non-mandatory continuous reporting
Jan 2020 to Jun 2020 (n=93) 451 2,485,700 1.81 Continuous surveillance, mandatory reporting
Jan 2019 to Dec 2019 (n=93) 1190 5,448,994 2.18 Continuous surveillance, mandatory reporting
Jan 2018 to Dec 2018 (n=86) 1229 5,138,087 2.20 Continuous surveillance, mandatory reporting
Jan 2017 to Dec 2017 (n=86)

1094 5,006,476 2.19 Continuous surveillance, Mandatory reporting
Jan 2016 to Dec 2016 (n=85) 1136 4,808,996 2.36 Continuous surveillance, mandatory reporting
Jan 2015 to Dec 2015 (n=85) 1061 4,643,404 2.29 Non-mandatory reporting
Jan 2014 to Dec 2014 (n=85) 1019 4,490,841 2.27 Non-mandatory reporting
Jan 2013 to Dec 2013 (n=85) 1031 4,329,896 2.38 Non-mandatory reporting
Jan 2012 to Dec 2012 (n=85) 1301 4,453,112 2.92 Non-mandatory reporting
Jan 2011 to Dec 2011 (n=84) 1201 4,449,487 2.70 Surveillance reporting commenced Oct 2010



Some differences between CDI surveillance and administrative data

 

Surveillance (VICNISS module)

Patient administrative data

Definition of CDI

Symptoms (3 or more loose stools in 24 hours) or ileus / toxic megacolon / pseudomembranous colitis (radiologically or on colonoscopy)ANDMicrobiological test confirmed (CDT / PCR positive) OR Pseudomembranous colitis (on scope / histopathology)  Admitted Patient Care National Minimum Data Set (APC NMDS)Diagnostic code ‘A04.7 Gastroenterocolitis caused by Clostridium difficile’ is used to identify separations affected by CDIPrincipal diagnosis describes the ‘primary’ condition resulting in admission of an individual to hospital.Non-principal diagnosis describes a condition that may have contributed to the hospital admission but was not the main reason for the admission. Non-principal CDI diagnoses were further filtered by Conditional Onset Flags (COFs). These are described as follows:
  • COF 1: Conditional Onset Flag 1, refers to a condition that has arisen during the episode of admitted care that would not have been present or suspected on admission
  • COF 2: Condition Onset Flag 2, refers to a condition that is previously existing, such as a comorbidity or chronic illness, or a condition suspected on admission, but is not the primary reason for the admission

Exposure Classification

Healthcare associated, healthcare facility onset (symptoms developed >48hours after admission)
Healthcare associated, community onset (symptom onset less than 4 weeks after last discharge from healthcare facility)
Community associated (symptom onset ≤ 48 hours of admission or onset while in community, >12 weeks since discharge from facility)
Indeterminate exposure (symptom onset ≤ 48 hours of admission or onset while in community, has been in community between 4 to 12 weeks)

Unknown - Lack of data
Patients whose CDI diagnosis arose during their hospital admission: non-principal CDI with a COF1





Patients admitted with pre-existing CDI symptoms coming into hospital from the community: principal diagnosis or non-principal CDI with a COF2). Note: does not identify location of disease acquisition

Severity of illness

  • History of  admission  to  an  intensive  care  unit  for  treatment  of  complications  from  CDI  (e.g.  shock that requires  vasopressor  treatment)
  • History of  surgery  (for  example  colectomy)  for  toxic  megacolon,  perforation  or  refractory  colitis
  • Death caused  by  CDI  within  30  days  of  symptom  onset.

 

Treatment review

  • Whether CDI specific  therapy  was  administered  ≤  72  hours  after  specimen  collection· 
  • Whether the  attending  physician  reviewed  the  patient’s  antibiotic  therapy  (other  than  CDI–specific  therapy) ≤  72  hours  after  specimen  collection.

 

 In the ACSQHC report, next steps will include an examination of the feasibility and benefits in continuing monitoring of the national burden of CDI in Australia using patient administrative data. Reviewing CDI surveillance data alongside antimicrobial prescribing and use data, infection data and environmental cleaning audit results, remains useful at state and territory, and hospital levels.

 

December 2021 - Impact of COVID-19 on hand hygiene compliance not sustained after improvement initiatives stopped

Stangerup and colleagues (Am J Infect Control 2021) conducted a single-centre quality improvement project in a Danish hospital; they report their findings on HCW hand hygiene (HH) compliance and the impact of COVID-19.

This study was conducted on a single orthopaedic ward where HCW wore sensors on name tags which connected to sensors on ABHR dispensers in clinical areas.  The network of sensors allowed identification of hand hygiene opportunities and events. The quality improvement activity had 3 phases;

Phase 1 (Jan to April 2019): Intervention – biweekly staff meetings with discussions of HH sensor data, accessible to head nurse and hygiene coordinator which were printed off as graphs and presented at HCW (doctor and nurses) biweekly staff meetings and on bulletin board.

Break (May to October 2019) – planned break for system upgrades

Phase 2 (November 2019 to March 2020): Pre-pandemic follow-up – No interventions but system switched on.

Unplanned break (April to September 2020)

Phase 3 (October to December 2020) –  Pandemic. Hand hygiene guidelines promoted

Hand hygiene compliance during phase 1 (intervention), phase 2 (pre-pandemic follow-up) and phase 3 (follow-up during COVID-19) was 58%, 46%, and 34%, respectively. In the patient rooms, the compliance was highest after patient contact compared with before patient contact during all the study phases.

The researchers conclude;

      • COVID-19 pandemic might not have a strong beneficial effect on HH compliance by HCWs as otherwise expected
      • HCWs fall back into old HH routines once improvement initiatives are stopped
      • Self-protection may be a major driver of HH compliance among HCWs which is in line with this study (and other literature) that found a higher HH compliance after compared to before patient contact
      • In this study, the number of HH opportunities were consistent over time which indicates that bundling of nursing activities and decreased room entry might not be the reason for changes in HH compliance. However, it is well-described that compliance decreases when gloves are worn which could be a factor in the findings of this study.


October 2021 - Case control study evaluating risk factors for SARS-CoV-2 outbreak amongst healthcare personnel at a tertiary care centre

Nosocomial transmission and hospital outbreaks among HCW have occurred due to delayed or missed diagnosis of COVID-19, often due to alternative diagnoses or limited testing capabilities or initial negative tests. Rosser et al (AJIC) have published findings of an outbreak investigation and case-control study of nosocomial SARS-CoV-2 transmission amongst HCP that occurred in a well-resourced academic medical centre that was found to originate in a non-intubated patient transferred from an outside hospital.

The index patient was admitted for management of a stroke following carotid endarterectomy. She had a background history of chronic pulmonary disease.  She was admitted a 214 square foot single room with excellent ventilation (approx. 20 air exchanges/hour).  She had a negative npa SARS-CoV-2 RT-PCR swab on day of admission. On Day 3, she developed acute respiratory failure. Alternative aetiologies were considered, but a RT-PCR test not repeated until Day 12 which was positive.  Over this period, she received HF oxygen (nasal cannula), CPAP and BiPAP.

A case-control study was undertaken as part of outbreak investigation by Infection Prevention and Control team.  All exposed HCW were tested for SARS-CoV-2 by RT-PCR ere invited to complete a voluntary survey to characterize their exposure to the index patient. The exposure window was defined as the patient's entire 12-day hospitalization. All individuals with a negative RT-PCR test who completed the survey and reported at least one day working with the index patient were included in the final analysis as controls.

Of 191 HCW were identified as potentially exposed and tested twice within 14 days of the last exposure; 9 ultimately tested positive for SARS-CoV-2. Whole genomic sequencing was performed on available samples from the index patient and 7 of the 9 HCP. A total of 12 SNPs were found and shared among all 8 samples. This showed 100% similarity amongst SARS-CoV-2 strains of the index patient and 7 HCP cases.

Risk factors evaluated for transmission included work type, PPE use, participation in various AGPs and non-aerosol generating procedures (non-AGPs), and duration of time spent with the patient. Compared to controls, cases had

  • significantly more patient contact time. All of the cases spent at least 2 days with the index patient compared to only 37/93 (39.8%) of controls. Similarly, 6/7 (85.7%) of cases had at least 3 patient contacts per day compared to only 31/93 (33.3%) of controls. 
  • significantly more likely to have performed airway procedures on the index patient, particularly placing the patient on high flow nasal cannula, continuous positive airway pressure (CPAP), or bilevel positive airway pressure (BiPAP) (OR=11.6; 95% CI=1.7-132.1).
  • PPE use:No one reported a breach in PPE and everyone reported using a procedure mask 100% of the time. Of the 7 cases, 6 reported never wearing an N95 but 5 of those 6 reported wearing protective eyewear and mask 100% of the time. 
  • Of 7 cases, there were 4 nurses, 1 nursing assistant, 1 speech therapist, and 1 physical therapist.

Of note, HCW COVID-19 vaccination status was not reported and while performing endoscopy and giving nebulizer treatments) were not significantly associated with transmission, the power of this analysis is severely limited as very few people performed these procedures in either group. The authors note that performing or being present during suctioning (in an open system) and adjusting oxygen were also activities statistically significantly associated with cases. They speculate that this may be a proxy for increased time spent with the patient but that it is possible that there is an increased associated risk with these other airway procedures that place HCW in close contact with airways secretions for extended periods of time.

This case reinforces the importance of repeated SARS-CoV-2 re-testing after admission in suspicious cases.  Subsequent to this event, the hospital implemented a new protocol requiring N95 masks (including eye protection) for all contact with a patient undergoing intermittent or continuous AGPs even with negative SARS-CoV-2 testing on admission.

October 2021 - Long-term clinical outcomes after COVID-19 infection

At the writing of this review, close to 70% of Australians >16 have received at least one dose of the COVID-19 vaccine (Australian Government Department of Health COVID-19 vaccine rollout update); and vaccine hesitancy across Australia is 17% (Melbourne Institute Vaccine Hesitancy Tracker). Vaccine hesitancy is higher in the 18-44 age group, compared to 45-64 and 65+ age groups.

Blomberg et al. (Nature Medicine) conducted a prospective long-term study of 312 COVID-19 patients from Bergen, Norway with median age, 46; 247 managed with in-home isolation and 65 hospitalized, together representing 82% of cases in first pandemic wave.  The most common comorbidities were asthma or chronic obstructive pulmonary disease (12%), hypertension (11%), heart disease (7%), rheumatic disease (6%), and diabetes mellitus (4%). At 6 months post-infection, 52% (32/61) of home-isolated young adults, aged 16–30 years, had symptoms at 6 months, including loss of taste and/or smell (28%, 17/61), fatigue (21%, 13/61), dyspnoea (13%, 8/61), impaired concentration (13%, 8/61) and memory problems (11%, 7/61). 

Long-term sequelae after moderate to severe COVID-19 are well documented however sequalae after mild infection is less well reported. This study suggests that in younger, healthier population groups, preventing or mitigating long-term COVID-19 sequelae through vaccination is also important. These data can be used to support medical discussions with vaccine hesitant individuals.   


August 2021 - Surgical site infections (SSI)

Surgical site infections (SSI) are one of the most common complications associated with surgery and are largely preventable. In Australia, SSI is the most common healthcare-associated infection occurring in approximately 3% of procedures. State-wide surveillance data from Victorian hospitals participating in the Victorian Healthcare Associated Infection Surveillance System (VICNISS) demonstrated an overall crude SSI rate of 2.8 per 100 procedures (2002-13). There are a range of recommended measures that should be in place to minimise patient risk link. The Victorian government has produced engineering guidelines for healthcare facilities on heating, ventilation and air-conditioning (HVAC) systems to satisfy internal environmental conditions for infection control link.

Sir John Charnley’s work in the 1960’s introduced the use of unidirectional (alternative term to “laminar”) airflow systems in theatres by reporting a significant reduction in SSI rates following hip replacements performed in unidirectional (UDAF) versus conventional air flow in theatres and also showing a strong correlation between SSI rates and the number of airborne bacteria sampled close to the wound site. In 2016, WHO provided updated recommendations link on intraoperative and postoperative measures to reduce SSI.  It included a recommendation that UDAF ventilation systems were not effective and should not be used to reduce the risk  of surgical site infection after prosthetic joint surgery.

Recent systematic reviews and meta-analyses of registry studies have continued debate on the use of UDAF systems on reducing SSI rates. What needs to be taken into consideration when interpreting the conclusions of individual studies and meta-analyses is separating out the effect of the ventilation system and other factors on reported outcomes (e.g., amount of air, filtration grade, size of the canopy, activity level, number of people, clothing system, surgical antibiotic prophylaxis, use of antibiotic-impregnated cement, patient BMI, ASA classification, blood loss).

These are two recently published systematic reviews in this area. The first looks at airborne bacteria levels within wound area during surgical procedures comparing laminar/ unidirectional airflow systems to turbulent/ conventional ventilation systems. The second looks at surgical site infection outcomes with the different types of operating-room ventilation. 

Ventilation design conditions associated with airborne bacteria levels within wound area during surgical procedures

Aganovic et al have published a systematic review link that identified 12 studies that looked at ventilation design conditions and intraoperative air sampling during real-time surgical procedures. The outcome that they examined was conditions where ultra-clean air (mean <10 cfu/m3) within 50 cm from the wound was achieved.

They report;

  • Studied articles demonstrate that high-volume UDAF systems perform as ultra-clean air systems and are superior to turbulent (TV) systems in reducing airborne bacteria levels close to the wound site.
  • Four different typologies of ventilation systems were identified: vertical UDAF (N= 8), turbulent ventilation (N = 11), mobile UDAF in combination with TV (N = 4), temperature-controlled airflow system (N = 1). 
  • Ultra-clean environments were reported in all UDAF-ventilated rooms compared with four of 11 operating rooms equipped with turbulent flow, and in three of four operating rooms with combined systems.
  • Other factors examined
    • On multivariate analysis, the total number of air exchange rates (P=0.019; odds ratio (OR) 95% CI: 0.66–0.96) and type of clothing material (P=0.031; OR 95% CI: 0.01–0.71) were significantly associated with achieving mean levels of airborne bacteria <10 cfu/m3.

They conclude;

(1) The effect of the type and the total number of air exchange rates of ventilation systems and clothing material was significantly associated with an ultra-clean environment (mean airborne bacteria load <10 cfu/m3) close to the wound (P<0.05).

(2) UDAF systems are superior to TV systems in reducing airborne contamination levels close to the wound site (P<0.05).

(3) UDAF systems considered had significantly higher air volume flows compared with TV systems considered.

(4) The number of door openings and number of persons present during surgical procedures had no significant impact on achieving an ultra-clean air environment (P>0.05).

(5) On multivariate analysis, the total number of air exchange rates (P=0.019; OR 95% CI: 0.66–0.96) and type of clothing material (P=0.031; OR 95% CI: 0.01–0.71) were significantly associated with achieving mean levels of airborne bacteria <10 cfu/m3 close to the wound.

(6) High-volume UDAF systems complying with DIN 1946-4:2008 standards for the airflow rate and ceiling diffuser size unconditionally achieve mean levels <10 cfu/m3 air close to the wound site.

 

The effect of operating theatre ventilation systems on SSI

In a review of literature to May 2020, Bao and colleagues link identified 14 studies with 590,121 operations (328,183 operations performed under laminar airflow ventilation and 261,938 performed under conventional ventilation).

Ten studies were related to surgical site infection in the total hip replacement; seven studies in total knee arthroplasties; and three studies in different abdominal and open vascular surgery. No significant difference was found between operation performed under laminar airflow ventilation and conventional ventilation in total hip replacement (OR, 1.23; 95% CI, 0.97–1.56, P = .09), in total knee arthroplasties (OR, 1.14; 95% CI, 0.62–2.09; P = .67), and in different abdominal and open vascular surgery (OR, 0.75; 95% CI, 0.43-1.33; P = .33). The impact of the type of operating room ventilation may have no influence on surgical site infection as a tool for decreasing its occurrence.

They did not perform a stratified analysis of studies that did and did not adjust for other SSI risk factors such as smoking, obesity, intraoperative temperature, glycemia, or cautery because no studies reported or adjusted for these factors.



June 2021 - Management of Peripheral Intravenous Catheters Clinical Care Standard

The Australian Commission of Safety and Quality in Health Care launched this new clinical care standard on 26 May.  This standard is comprised of ten quality statements (arranged in order starting from QS1 assessing IV access need to QS10 safe removal and replacement if needed), each with suggested indicators for local monitoring.

At the launch webcast, it was noted that

  • PIVC insertion in hospitalised patients is very common (up to 70%)
  • Many are not used after insertion (4-28%, up to 50% in ED)
  • Complications are common (up to 69%)

This CCS highlights three key areas for improvement

  • Reducing number of unnecessary PIVC insertions
  • Reducing number of cannulation attempts
  • Reducing number of PIVC infections and complications

This CCS does not cover

  • specialised decision-making for PIVC insertion (such as during anaesthesia, light sedation, short-term cannulation for diagnostic imaging purposes, acute resuscitation and acute trauma management) – PIVC inserted in these situations are short-term and expected to be removed same day
  • PICCs, mid-line catheters, CVCs

The panel were asked to comment on how long PIVC should remain in; it was recognised by panellists that the approach should be setting specific and there is no one size fits all answer.  A Cochrane review that suggested removal when clinically indicated rather than routine was safe practice was discussed.  It was also noted that routine removal at 72 hours is often practised reflecting a balance between risk of bloodstream infection and frequent PIVC changes.

June 2021 - Vaccine breakthrough infections with SARS-CoV-2 variants

In this NEJM case report, Hacisulyman et al describe two cases of vaccine breakthrough infection.  Of a cohort of 417 fully vaccinated persons at Rockefeller University, New York City (persons received a second dose of BNT162b2 (Pfizer–BioNTech) or mRNA-1273 (Moderna) vaccine at least two weeks previously), they identified two women with vaccine breakthrough infection. Specimen testing included saliva testing (for detectable viral RNA by RT-PCR and viral load calculation, targeted sequencing and whole genome sequencing) and serum (for neutralisation antibody titres).

Patient 1 was a healthy 51-year-old, who 19-days post second dose, developed sore throat, congestion and headache, and lost her sense of smell the next day.

Patient 2 was a healthy 65-year-old woman who was diagnosed 36-days post second dose and 14-days after her infected partner tested positive.  Her symptoms were fatigue, congestion and headache.

Examination of the SARS-CoV-2 sequences revealed that both patients were infected with variant viruses. Rapid identification of sequence variants by targeted PCR amplification showed that neither sequence precisely fit any known clade. Viral sequencing revealed variants of likely clinical importance, including E484K in 1 woman and three mutations (T95I, del142–144, and D614G) in both.

Considering the clinical history, time course, and neutralizing antibody titres measured, it was felt that it was very likely that both patients had demonstrated effective immune responses to the vaccines. In addition, data from Patient 1 indicated that infection with variant virus could be sustained with a high viral load despite having high levels of neutralizing antibodies to variants.

The authors concluded that these observations indicate a potential risk of illness after successful vaccination and subsequent infection with variant virus, and provides support for continued efforts to prevent and diagnose infection and to characterise variants in vaccinated persons.



April 2021 - Influenza vaccination uptake of healthcare workers in Victorian public health services and aged care homes

In March’s Australasian Society of Infectious Diseases (ASID) conference, VICNISS’ Alex Hoskins, Noleen Bennett and Leon Worth presented a review of historical influenza vaccine uptake of Victorian HCWs and compared these with more recent influenza vaccination uptake by workers within the aged care sector. This was awarded Vaccination Special Interest Group (VACISG) best poster available, for viewing here

Victorian public healthcare facilities performed an annual period prevalence survey of HCW influenza vaccination compliance from 2014 to 2020. All Victorian public aged care homes commenced a similar survey in 2018.

The target rate for the Victorian acute sector influenza vaccination campaign has increased over seven years from 75% in 2014 to 90% in 2020. Influenza vaccination uptake has increased from 72.7% in 2014 to 93% in 2020.  A significant contributor was the inclusion of HCW influenza vaccination uptake as an annual key performance indicator for Victorian hospitals. In Victorian public sector aged care homes, influenza vaccination uptake has increased from 86.9% in 2018 to 88% in 2019.  It was 98.8% in 2020 when mandatory influenza vaccination was initiated as part of COVID-19 State of Emergency in Victoria.

The authors conclude that future policy directives including mandatory HCW vaccination, should proceed with acknowledgement of the potential benefit of including a range of vaccine preventable diseases as performance indicators. In March 2020, legislation was passed that mandates the vaccination of all Victorian HCWs. Whilst existing Victorian policy supports this legislation, the legislation has not as yet been enacted.


April 2021 - Impact of a C. difficile infection (CDI) reduction bundle and its components on CDI diagnosis and prevention - more to learn

Blanco et al publish the outcomes of a pilot a computerized clinical decision support-based intervention bundle and conducted detailed evaluation of several intervention-related measures into the impact of CDI reduction bundle (American Journal of Infection Control 49: 2021; 319−326).

An interrupted time series analysis was used to evaluate impact on hospital-onset (HO)-CDI.

It was conducted in two hospitals in Maryland, US from October 2016 to June 2018, including pre- and post-implementation period.

To improve efficiency of multiple interventions, the bundle leveraged the use of computerized clinical decision support (CCDS) for implementation. CCDS tools provide patient-specific data to clinicians through the electronic medical record (EMR) at the point of care and decision-making.

The intervention bundle included:

(1) institution of enteric precautions at initial suspicion of CDI before test results are returned (e.g., linking electronic enteric precautions to order for CDI test),

(2) optimization of C. difficile testing via decision support at the time of electronic order entry (e.g., inappropriate test ordering prompts included tests ordered in patients who did not meet diarrhea criteria (≥3 loose stools in 24 hours), received laxatives within 48 hours before the test, had a previous C. difficile positive result in the last 21 days or a negative result in the last 5 days).

(3) decreasing unnecessary prescribing of proton-pump inhibitors (PPI) (e.g., incorporating mandatory PPI indication in PPI prescribing orders, PPI removal from order sets),

(4) reducing the use of selected high-CDI risk antibiotics (fluoroquinolones, third generation cephalosporins, and clindamycin) (e.g., implementing antibiotic guideline and order set changes to favour lower CDI-risk antibiotics, shorter duration of treatment), and

(5) optimization of CDI-related disinfection with use of a sporicidal agent for environmental cleaning

This C. difficile Infection reduction bundle showed variable impact. Placement of CDI suspects in enteric precautions before test results did not change. Only hospital B decreased the frequency of CDI testing and reduced inappropriate testing related to laxative use. Both hospitals reduced the use of PPI and high-risk antibiotics.   A 75% decrease in hospital-associated C.difficile infection post-implementation was observed for one of the hospitals. The authors concluded that differences in hospital-specific uptake of bundle elements may explain differences in effectiveness.

Whilst these study findings do not have definitive findings, it is important to note that it had a unique multifaceted approach to identifying measures to reducing CDI under endemic conditions, using CCDS where possible, and in measuring the extent to which each component was implemented.  Published bundles to reduce CDI frequently lack information on compliance with individual elements. Collectively these findings demonstrate the need to critically evaluate processes and intermediate outcomes and deconstruct bundled interventions, to better measure both effectiveness and gaps.




February 2021 - Longer term consequesnces of COVID-19 infection - more to learn.  

Longer term consequences of COVID-19 infection - more to learn

COVID-19 is a new disease and uncertainty remains regarding the possible long-term health sequelae. This study by Huang and colleagues in the Lancet reports on sequalae at 6-month follow up in hospitalised patients (6-month consequences of COVID-19 patients discharged from hospital: a cohort study); the cohort comprised 1733 adult patients discharged from a hospital in Wuhan (48% women, 52% men; median age 57·0 years, IQR 47·0–65·0; 4% admitted to ICU).

Six-months post-illness onset, 76% (1265 of 1655) of the patients reported at least one symptom that persisted

  • Fatigue or muscle weakness was the most frequently reported symptom (63%), followed by sleep difficulties (26%)
  • 390/516 selected sub-group of patients attended for follow-up pulmonary function testing, CT chest and US lower limbs
    • 52% of patients had residual chest imaging abnormalities (the most common patterns were pulmonary interstitial change with ground glass opacities and interstitial lines).
    • Disease severity during the acute phase was independently associated with the extent of lung diffusion impairment at follow-up (odds ratio 4·60, 95% CI 1·85–11·48), with 56% (48 of 86) of patients requiring high-flow nasal cannula, non-invasive ventilation, and invasive mechanical ventilation during their hospital stay having impaired pulmonary diffusion capacity
    • No DVT were identified on follow-up testing

To date, this is the largest published cohort study examining the longer-term outcomes post-COVID-19. This study cohort represents hospitalised patients rather than the majority of COVID-19 cases that are diagnosed in the community who do not present for acute hospital care.  Given the clinical spectrum of SARS-CoV-2 infection is wide encompassing asymptomatic infection, fever, fatigue, myalgias, respiratory tract illness that can range from mild to severe, the range of long-term sequelae may be different in this cohort to hospitalised patients. This study adds to the emerging literature that demonstrates that there is a need for outpatient clinics dedicated to following up on and supporting patients who have had COVID-19 with longer-term sequelae.

February 2021 - Systematic review findings that up to one-third of COVID-19 infections are asymptomatic

A systematic review (Annals of Int Med. 22 Jan 2021.The Proportion of SARS-CoV-2 Infections That Are Asymptomatic) suggests that at least one-third of COVID-19 infections occur in people who never develop symptoms, providing strong evidence for prevalence of asymptomatic infections. Asymptomatic COVID-19 infections are defined as infections in people  with a positive test result that do not develop COVID-19-related symptoms, a diagnosis that can only be made only after 14-days of follow-up.

Oran and Topol identified 61 eligible studies and reports; 43 using PCR nasopharyngeal testing and 18 using antibody testing to identify current or prior infection. 14 studies presented longitudinal data with information on evolution of symptomatic status where nearly three-quarters tested positive but had no symptoms at the time of testing and remained asymptomatic on follow-up. Highest-quality evidence came from serosurveys in England (n=365,104) and Spain (n=61,075) which suggested up to one-third of infections are asymptomatic. In a cross-sectional study of Belgian long-term care facilities (n=280,247), age did not seem to affect proportion of persons who were asymptomatic which were similar in staff (median age 42 years) compared to residents (median age 85 years).

The authors postulate that limitations of serosurveys  includes (1) an onus on the study participant to accurately recall symptoms retrospectively and that symptoms or bodily sensations such as anosmia may be subtle (2) PCR tests may be affected by false-positive results.

As the first-generation of COVID-19 testing is rolled out world-wide, more research will be needed to determine their efficacy in preventing asymptomatic infection.

 

February 2021 - A special review: Introducing concepts in interpreting the numbers in COVID-19.

A key recommendation for controlling the COVID‐19 pandemic is to “test, test, test”; this is important in Australia’s asymptomatic testing and contact tracing activities. As Infection Prevention and Control experts, it is important for us to understand how SARS CoV-2 test performance and current prevalence of COVID-19 in the community influences public health recommendations.
As Bell and colleagues discuss (MJA 1 Feb 2021 How to use imperfect tests to guide decision making) tests are rarely 100% sensitive and 100% specific, and usually there is a trade‐off between the two.  As a reminder, sensitivity is a measure of how many cases the test diagnoses of all true cases, and specificity measures the ability of the test to only diagnose true cases (a highly specific test will produce very few false positives). False positives can be a particular problem if, for example, a test for COVID-19 also detects other coronaviruses. Likelihood ratios (LR) can be calculated using a test’s sensitivity and specificity.
The process of making a diagnosis can be thought of as an estimation and re‐estimation of the probability of disease in a continuous process. We are stepped through some scenarios showing this process.
  (a) 26yo from Bondi, Sydney in late March with respiratory symptoms
      1. Pre-test probability 6% (this is determined by an estimation of the person’s risk based on known epidemiological information such as exposure risk/ local or community transmission)
      2. COVID-19 PCR (reported as SARS CoV-2 RT-PCR in the literature) nasopharyngeal swab result is negative -> negative LR of test 0.41 (see below for explanation)
      3. By applying Fagan’s nomogram (Fig 1), post-test probability 3%
      4. Decision threshold: Continue to self-isolate, repeat test
  (b) 26yo from Bondi, Sydney in late March with respiratory symptoms, has had one negative COVID-19 nasopharyngeal swab
- Pre-test probability 3%
- COVID-19 PCR nasopharyngeal swab result is negative -> negative LR of test 0.41
- By applying Fagan’s nomogram (Fig 1), post-test probability 1%
- Decision threshold: no further requirements for testing or isolation required once symptoms resolved
Comment:
The main difference influencing the outcome (decision threshold) between scenarios (a) and (b) is the “one negative COVID-19 test” in this situation. However, there could be an alternative scenarios where the pre-test probability remains high (6% or more) even with one negative PCR result e.g. person was a household contact of someone who was COVID-19 positive or the test had a poorer performance (lower LR) and was more likely to miss infections e.g. PCR saliva compared to nasopharyngeal test.
The key considerations are:
    1. Pre-test probability
      • This is based on the current known prevalence of COVID-19 in the community
    2. Likelihood ratio (LR) of a given test result in a patient with disease compared to a patient without disease (using Fagan’s nomogram)
    • For every test, a positive LR can be calculated to decide on implications of a positive test result (LR+ = probability of positive test in diseased person / probability test positive in non-diseased person), and a negative LR for implications of a negative test result (LR- = probability of negative test in diseased person / probability test negative in non-diseased person).
    • When the LR is >1, the probability of disease after receiving a test result (post-test probability) is increased from what it was before the test (pre-test probability)
    • The higher the LR, the more powerful the test is at shifting the probability of disease upwards from pre-test to post-test
    • SARS CoV-2 RT-PCR test LR are based on published data on performance of test looking at sensitivity, specificity, positive and negative LR; in the scenario above the LR is based on summary findings from published SARS CoV-2 RT-PCR nasopharyngeal test performance; the LR would change if the test changed to SARS CoV-2 saliva testing or serological tests.
    1. Post-test probability
      • Determine by applying pre-test probability and LR to Fagan’s nomogram (Fig.1)
    2. Decision threshold
      • They are thresholds set to be met against specific Public Health recommendations
From Bell K et al. Med J Aust 2021, 214(2);69-73.

Notes
1. Fagan's Nomogram modified from Figure in JAMA 1994;27(9):703-707.  To use the nomogram, draw a straight line from the pre-test probability for the patient (left-hand side) through the likelihood ratio for the patient's test result (middle) to arrive at the estimated post-test probability of disease (righthand side).
2. Depicts Scenarios 1 from Table 2:  26 year old man from Bondi presents with blocked nose, cough and fever, pre-test probability 6%.
3. Blue line (1A): First PCR test negative, negative likelihood ratio=0.41,post test probability=3% (1A from Table2)
4. Red line (1B): Second PCR test negative, post test probability = 1% (1B from Table 2)


December 2020 - Two recently published articles on seroprevalence of SARS-CoV-2 antibodies

The Australian Government has endorsed serosurveys as a core component of the national COVID-19 SurveillanceIn May, the Australian Government has endorsed serosurveys as a core component of the national COVID-19 Surveillance PlanGovernment endorsed serosurveys as a core component of the national COVID-19 Surveillance Plan, in addition to case-based reporting, targeted active case finding and syndromic and sentinel surveillance (https://www.health.gov.au/resources/publications/australian-national-disease-surveillance-plan-for-covid-19). It should be noted that antibody prevalence is not currently a measure of population protection as we do not yet know whether or for how long antibodies protect people against re-infection.

https://www.health.gov.au/resources/publications/australian-national-disease-surveillance-plan-for-covid-19

Serosurveillance complements epidemiological data collected using case reporting based on detection of the virus.  Reported COVID-19 cases represent an underestimate of the true number of infections in the population; this can relate to a proportion of people with SARS-CoV-2 infection who do not develop symptoms, have mild symptoms or do no not attend testing services for diagnosis by nucleic acid testing.  Serological surveys (serosurveys) measuring the prevalence of SARS-CoV-2 antibodies in specific sub-populations (e.g. by age, health care workers, ATSI people, communities over time), before, during and after epidemic peaks, can help estimate proportion in those groups that have previously been infected.  Serosurveys have been undertaken in many countries, using a variety of testing methodologies.

These are two recently published articles on seroprevalence of SARS-CoV-2 antibodies and how this data may be used to help monitor seroprevalence in populations of importance and help inform public health strategies. The first is from Sydney and the second is a systematic review and meta-analysis of published literature on seroprevalence in HCW to 24 August 2020.

1.  Seroprevalence of SARS-CoV-2-specific antibodies in Sydney, Australia following the first epidemic wave in 2020

Gidding and colleagues (MJA, 11 November 2020) report on the first comprehensive assessment of SARS-CoV-2 seroprevalence in Australia undertaken, based on a survey of antibody prevalence amongst three sub-populations in Sydney following the first COVID-19 wave in Australia. Notifications were identified from March to April in NSW, peaking in the fourth week of March; where in this NSW surge 60% were detected in returned travellers many who appeared to be in quarantine and community transmission appeared to be sporadic then widespread.

 

The sub-populations where serosurveys were undertaken were in (1) 20-39 year old women undergoing antenatal screening (2) 20-69 year-old plasmapharesis blood donors and (3) people of all ages having selected blood tests at selected pathology services; from individuals living in specific postcodes in Greater Sydney LGAs.  Details on testing (all at a single reference laboratory) and statistical analysis undertaken to allow estimation of the true proportion seropositive in each subpopulation are provided in the report.

 

The outcome measure of interest was the proportion of participants in each of these groups testing positive for anti-SARS-CoV-2-specific IgG antibody (adjusted for test sensitivity and specificity). The seroprevalence at this timepoint was under 1% in all three sub-populations; which was interpreted as supportive of a finding of limited community transmission during first epidemic wave in Sydney. Of interest, a detailed breakdown of SARS-CoV-2 antibody profiles of seropositive individuals in this study; 63% seropositve by IFA also had evidence of neutralising Ab which may represent false positive result by IFA or milder infection (other studies predominantly in hospitalised patients have reported >90% had evidence of neutralising Ab).

2. Seroprevalence of SARS-CoV-2 antibodies and associated factors in health care workers : systematic review and meta-analysis

It is postulated that knowing seroprevalence of SARS-CoV-2 antibodies among health care workers (HCW) provides important information to understand COVID-19 spread among health care facilities and to assess the success of public health interventions. Galanis and colleagues (J of Hosp Inf, 16 Nov 2020) undertook a systematic and review and meta-analysis of published literature to 24 August 2020 to determine the seroprevalence of SARS-CoV-2 antibodies among HCW and associated factors. They identified forty-nine studies (14 of which were available in pre-print, prior to peer-review process), including 127,480 HCWs. The majority of studies were from Europe (31), then North America (9), Asia (6) and Africa (3).  There were no identified studies from Australasia. 

The estimated overall seroprevalence of SARS-CoV-2 antibodies among HCWs was 8.7% (95%CI: 6.7-10.9%). Seroprevalence was higher in studies that were conducted in North America (12.7%) compared to those in Europe (8.5%), Africa (8.2), and Asia (4%). In Europe overall seroprevalence was 8.4%, where seroprevalence in studies in United Kingdom (n=7) and Italy (n=8) was higher (10.3%) than reported

seroprevalence in studies in Germany (n=5) and Greece (n=2) 2.2%.  The following factors were associated with seropositivity in HCW:  male genderBlack, Asian, and Hispanic HCWs, work in a coronavirus disease 2019 (COVID-19) unit, patient-related work, frontline health care workers, health care assistants, personal protective equipment, self-reported belief for previous SARS-CoV-2 infection, previous positive PCR and being a household contact of someone with suspected or confirmed COVID-19.

The authors postulate that differences in seroprevalence might be explained by differences in

adherence to infection prevention and control measures and the appropriate use of

personal protective equipment among HCWs bearing in mind the following limitations of their meta-analysis:

  • 14 out of 49 included studies were published in pre-print services which do not apply peer-review process
  • Heterogeneity between results was very high. Quality assessment of prevalence studies, cross-sectional studies and cohort studies was assessed where quality was moderate in 37 studies, good in 10 studies, and poor in two studies. Subgroup analysis noted that seroprevalence of SARS-CoV-2 antibodies was higher for the studies with poor quality (11.6%) compared to those with moderate quality (8.8%) and good quality (7.9%) indicating that difference in study quality could be a significant reason for difference in seroprevalence.
  • Seroprevalence reported in studies could be underestimated or overestimated depending on the applied antibody test. Validity (sensitivity and specificity) of the antibodies tests was not reported in most of the included studies. Galanis et al performed validity assessments for the antibodies tests used in the included studies according to the manufacturers data; sensitivity ranged from 50% to 100%, while specificity from 80.5% to 100%.
  • Time between exposure and antibody testing in studies is unknown and seropositivity may have been missed if testing was too early. This could result in an underestimation of the seroprevalence.



October 2020 - Special report on COVID-19 Outbreaks in Aged Care Facilities

Since the 4 May 2020, there have been over 170 COVID-19 outbreaks in Victorian aged care facilities (225 of all Victorian RACF); these constituted 5% of total infections in Victoria at the beginning of July, around 30% in August and 40% in September. In total, over the last 6 months, there have been 4,626 cases linked to RACF outbreaks; 2,663 (58%) in staff/household members, 1,963 (42%) in residents. 43% of the outbreaks have been 1 week or less (from first to most recent COVID diagnosis); however 27% have been up to 3 weeks, 23% 4 to 7 weeks, and 8% longer than 7 weeks.

I have been seconded to the Victorian Aged Care Response Centre (VACRC); the centre was established on 27 June with representation from Commonwealth Department of Health, Aged Care Quality and Safety Commission and the federal and state governments.  VACRC has provided support to outbreak facilities
    • Workforce support
    • Zoning, IPC, cleaning
    • Waste management
    • Repatriation of staff and residents back to facilities with extended outbreaks
VACRC has undertaken over 650 prevention visits to non-outbreak facilities to perform an assessment of facility COVID-preparedness and also provide PPE training using train the trainer model. The most common items that required addressing
    • 31% - designating areas for care of COVID suspected/confirmed residents separated from other residents, including floorplan identification of donning/doffing stations and outbreak zones
    • 14% - workforce planning not in place to support workforce furloughing
    • 9% - PPE use (use of mask and face shield in clinical areas)
    • 12% - hand hygiene product availability in all areas of the facility
    • 17% - signage of occupancy in communal staff areas, including tearooms

Some of the lessons learnt around COVID-19 preparedness include:

Infection Prevention & Control

Preparation

In event of outbreak

PPE use Refresher
Train the trainer
Face to face
Planning for training new staff, agency
Buddying up
Support person
Training new staff, agency
Hand hygiene availability Readily available throughout facility
In resident areas, in each resident’s room and outside room; or readily accessible for staff to be able to perform hand hygiene appropriately on entering and leaving resident zone
Ensure sufficient supply and monitoring  including staff communal areas
Zoning Floorplan identification of key zones/ areas (red, orange, green zones)
Desk-top exercise for following scenarios
1 resident, 1-4 residents, >4 residents1 room, > 1 room, Outbreak zone
Floorplan needs to be readily available
Consider: residents with cognitive impairment, wandering behaviours or dementia
Consider: Layout of facility
Implement
Floorplan should identify the following Donning and doffing stations
Entry/ exit points
Meal delivery
Laundry removal
Waste removal
PPE storage
Planning to ensure equipment (e.g. food trays, medicine trolleys, slings) do not cross zones
Physical distancing Yes
Staff communal areas Signage maximum number of persons in room
Split breaks
Doffing and redonning stations on entry and exit
Remove mask to eat and drink only
Have break outdoors if weather allows, appropriately physically distanced
Yes
Staff cohorting

October 2020 - Victorian Healthcare Worker COVID-19: An update

Healthcare Worker Infection Prevention and Wellbeing Taskforce has been set up to provide advice to the department on protecting healthcare workers.
To 6 October 2020, 3,538 COVID-19 cases have been in Victoria’s healthcare workers (HCW); of these 73% were acquired in a healthcare setting, 14% not in a healthcare setting, 13% unable to be determined. Of HCW acquiring COVID-19 in healthcare setting; 50% are aged care or disability workers, 40% nurses or midwives, 5% medical, 5% other HCW.

In August, Victoria’s advice on N95 respirators was expanded to go above the National Guidelines due to observed risks in some of our health services where patients with coronavirus (COVID- 19) were being cohorted in wards. Our guidance also sits above the current guidance of the CDC (USA), UK and WHO for PPE use in hospital and aged care settings.

An update was provided on latest announcement on 17 September 2020 and included
  • Announcement of the Respiratory Protection Program to assist health services in implementing structured interventions and prevention strategies (such as  fit testing)
  • Improving COVID Safe workplaces with challenges noted by health services including
  • PPE use – related to fatigue of staff in maintaining good practices
  • Cleaning - of high number of touch points and shared contact points (i.e. shared clinical equipment, telephones, computers)
Research into transmission risk in COVID-19 wards to inform input from Taskforce to minimum standards being developed by the department:
  • Number of patients in COVID-19 wards
  • Cleaning procedures for COVID-19 wards
  • Staff rostering in COVID-19 wards
  • Best practice approaches for PPE use



August 2020  - (1) Managing teamwork in the face of COVID-19 pandemic 

(1)Managing teamwork in the face of COVID-19 pandemic

We are living in extraordinary times, facing unprecedented challenges that they can only overcome by responding, learning and adjusting as a team. Tannenbaum et al provide evidence-based tips based on extensive studies (close to 50 meta-analyses) and experience of teams that work under high-stress conditions where the consequences of failure and personal pressures are high (e.g. trauma teams, astronauts, soldiers)

A summary of some key points:


Recognise wins and successes—large and small. During the pandemic, teams may be overwhelmed by high patient volume, scarce resources and challenging cases. Repeated exposure to and a sole focus on problems, mistakes, obstacles and undesirable consequences drains collective efficacy. During COVID-19, reminders about successes, signs of progress and obstacles overcome are needed to retain a sense of “collective” efficacy.


Ensure the team sustains a shared mental model, a shared understanding, about roles and priorities. Not every team member must know the exact same thing, when work tempo is high and new processes are being adopted, a ‘common enough’ understanding of key elements can be achieved by quick, periodic prebriefs, debriefs and huddles as well as thoughtful handoff. These act as touchpoints to share current priorities, clarify responsibilities and decision authority and confirm who has the most expertise/latest information related to key needs. Questions can help a team sustain a shared perspective: often when one team member is uncertain, others are as well, so all team members can benefit from hearing the answer.


Don’t forget the people behind the scenes. HCW providing hands-on patient care during the pandemic have rightly been referred to as heroes. It is also important to recognise that others are continuing to work behind the scenes, ensuring supplies are procured, families are updated, information systems remain functional, non-COVID patients are cared for, areas are cleaned and so on.

Take actions that build and sustain psychological safety. Research shows it is one of the strongest predictors of team effectiveness (Google found it to be the top predictor in their teams). Psychological safety is the extent to which team members perceive that they can take interpersonal risks such as speaking up, admitting a mistake, acknowledging confusion and offering a dissenting opinion without undue risk of being punished or rejected.


Help team members address concerns with their ‘home team’. Team members may be worried about bringing home the virus, and may be dealing with financial, childcare or healthcare concerns at home. These stressors are very difficult to combat strictly within a team, and often require attention at the organisational level.

Consciously boost team resiliency. A highly resilient individual can personally withstand pressures but that does not mean they will monitor or support teammates who are under stress. Team resilience is the capacity of a team to withstand and recover from adversity, and it operates differently from individual resilience. Highly resilient teams take intentional actions to minimise, manage and mend from stressful events by anticipating and preparing for challenging events. Leaders help manage stressors by accurately assessing emergent challenges, guiding the team smartly to and from ‘normal’ and ‘emergency’ modes and providing timely updates. Team members can boost team resilience by taking actions to mend after a troubling event, which can include learning from the experience.

 
August 2020 - Responding to the COVID-19 pandemic in long-term care


(2) Responding to the COVID-19 pandemic in long-term care

The WHO have recently published a policy brief (WHO Preventing and Managing COVID-19 across Long-term Care Services) that highlights the challenges and required actions to mitigate the impact of COVID-19 on long-term care facilities (LTCF). This is a major issue in Victoria currently in our aged care facilities.
As we are aware, COVID-19 disproportionately affects older people: in many countries more than 40% of COVID-19 related deaths have been linked to LTCF. The evidence shows that once COVID-19 infection is present in the facility, it is difficult to control in part due to a large number of people living in close proximity and also for staff required to provide continuous, complex care with high levels of physical and emotional contact. As well, there is also increasing evidence of potential transmission from presymptomatic or asymptomatic people who have COVID-19; studies of outbreaks worldwide show that between 7% to 75% of residents and 50% to 100% of staff who are test positive fall into these categories.
This WHO policy brief outlines policy objectives to mitigate COVID-19’s impact in terms of our national response and also drills down to key actions at a local level.

The identified challenges include:


    • Pre-existing workforce shortages amplified by COVID-19, high staff turnover impeding continuity of care and consistency of IC measures
    • Difficulties adapting to increased health care needs of residents
    • Access to secure and sustained supply of PPE, training of staff
    • Lack of systematic monitoring of health status of residents and staff
    • Movement restrictions and other shielding measures are relatively easy to implement but may have an enormous impact on the well-being of the residents, in particular, residents with dementia
Recommended actions include:
    • Establishing a surveillance system monitoring COVID-19 incidence in residents and deaths; to use this data is used in real-time to refine government policy
    • Ensure secure and adequate supply of PPE to protect staff
    • Provide adequate training guidance and routine training of staff and caregivers
    • Oversight of appropriately trained personnel delivering essential services to facilities
    • Development of clear COVID-19 care pathways, including for transfers for residents with COVID-19 and non-COVIOD-19 symptomsEnsure facilities are supported by primary care service, have access to rapid response teams (such as Outreach services with geriatric and palliative care expertise)
    • Ensure facilities upskilled when required to coordinate and collaborate with DHHS in effective contact tracing
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June 2020 - COVID-19 resources:  ACSQHC

Following a National Cabinet decision, Australian hospitals have commenced easing restrictions on elective surgery, investigations and procedures from 27 April 2020. Health service organisations are required to prepare and implement an organisation-wide Risk Management Strategy to manage and reduce the risk related to the transmission of COVID-19.The Australian Commission on Safety and Quality in Health Care (ACSQHC) has developed resources to support health services to implement these requirements.

It includes position statements on elective surgery and IC precautions:

COVID-19: Elective surgery and infection prevention and control precautions 

There are frequently asked questions for clinicians, consumers, patients and carers to understand what the changes mean for them:

FAQs for clinicians on elective surgery

FAQs for consumers on elective surgery

There are posters:

Infection prevention and control Covid-19 PPE poster

Special precautions for Covid-19 designated zones poster

June 2020   - COVID-19 resources:  National COVID-19 Clinical Evidence Taskforce

This resource is important to support health professionals in keeping up to date with the large number of COVID-19 research activities and results around the world. Taskforce recommendations have wide endorsement from 26 member organisations covering primary, acute and critical care settings including ACIPC and ASID and is in partnership with ACSQHC.

A snapshot of COVID-19 research activities (as of 1/6/20)

• 6361 studies published (intervention, diagnosis and prevention), 1149 added this week

• 1313 clinical trials registered (74% RCTs), 209 added this week

• 16 randomised controlled trials published, 1 added this week

• 1050 systematic reviews registered, 75 added this week

Current areas under review by the taskforce include;

• The use of remdesivir as a disease-modifying treatment

• Safety of hydroxychloroquine

• Timing of mechanical ventilation

• Tracheostomy

• The use of corticosteroids

• Recommendations for children and adolescents

• Recommendations for pregnant and perinatal women

What is the significance of positive SARS-CoV-2 RT-PCR testing post-discharge?

(1) Chinese study 

Nearly 16% of 69 patients discharged from a Chinese hospital after recovering from COVID-19 had positive results on real-time reverse-transcriptase polymerase chain reaction (RT-PCR) tests after discharge, according to this study (Hu et al. JAMA Netw Open. 2020;3(5):e2010475). Positive results occurred between 9 and 17 days after discharge; none of these patients had symptoms at the time of testing.

(2) KCDC investigation report 

In press release from 19/5/20, the Korean Centre for Disease Control (KCDC) report their findings from investigation and analysis of re-positive cases (defined as “cases that test SARS-CoV-2 RT-PCR positive after being discharged from isolation”). Of 447 re-positive cases, further epidemiological investigation was undertaken in 284 and the following reported;

• Data from three groups of patients from different cities showed that between 25.9% and 48.9% of patients again tested positive after they had been discharged.

• Among the 226 patients who were symptomatic when their case was initially confirmed, a repeat positive test result after discharge occurred an average of 44.9 days (range, 8 – 82 days) from the date symptoms initially developed. It took an average of 14.3 days (range, 1 – 37 days) from the time of discharge to the time of the second positive test

• Of those who again tested positive, 44.7% (n=126) had symptoms that included cough and sore throat (results of re-testing for other respiratory viruses were not reported)

• In all neutralizing antibody production was found from the first serum

Of the 284 cases, 108 re-positive cases had samples collected for vial cell culture testing (it is noted that the Ct values for the RT-PCR during re-positive period was >30 for 89.5% of cases)

• Viral cell culture testing of all 108 samples were negative for SARS-CoV-2

• Of note, Ct values for the RT-PCR was >30 for 89.5% (n=68) of samples

The KCDC advisory committee concluded on the basis of these findings that persons who are discharged from isolation after recovering from COVID-19 and who again test positive for SARS-CoV-2 are unlikely to be infectious and under KCDC revised protocols from 19/5/20 no additional tests are required for cases that have been discharged from isolation.

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February 2020 - Novel coronavirus (2019-nCoV)

(*NB: This information was up to date and current at the time of publication however as this is a rapidly changing situation please refer to the links mentioned in the review for any further updates as information becomes available)

On December 30th 2019, a cluster of cases of pneumonia of unknown origin was identified by authorities in Wuhan, China.  On January 7th 2020, novel coronavirus (2019-nCoV) was isolated.  As of February 2nd 2020, health authorities in China have reported more than 12,000 cases and 259 deaths. Confirmed cases have been identified in mainland China, as well as 26 other countries including Hong Kong, Macau, Taiwan, Thailand, Japan, Malaysia, South Korea, Vietnam, Cambodia, Sri Lanka, Singapore, Nepal, France, Italy, Germany, USA, Canada and Australia. The World Health Organisation declared on January 30th 2020 that the outbreak of 2019-nCoV constitutes a Public Health Emergency of International Concern.

The situation is evolving rapidly as we find out more about this new virus.

DHHS alert: update 2/2/20

  • As of 1 February 2020, the case definition for a person suspected to have contracted novel coronavirus (2019-nCoV) has been expanded to any person who has an acute respiratory infection and has been in mainland China or had close contact with a confirmed case of novel coronavirus in the 14 days prior to onset of illness.

  • People who have been in mainland China (excluding Hong Kong SAR, Macau and Taiwan) are advised to self-isolate if they were in mainland China on or after 1 February 2020.

  • The requirement to self-isolate continues to apply to people who have been in Hubei Province, China, for 14 days after they left Hubei Province.

  • Anyone who has been in close contact with a confirmed case of 2019-nCoV should also stay at home and avoid public settings until 14 days after their last contact.

  • The department has confirmed four cases of novel coronavirus in Victoria.

  • Be alert for patients who meet the updated case definition, ensure they wear a surgical mask and place them in a negative pressure or single room.

  • Take a travel history in patients with respiratory symptoms. Note the updated case definition to inform testing.

  • Notify the Department of Health and Human Services on 1300 651 160.

Links to resources on 2019-nCoV

For Victorian Department of Health and Human Services regular updates and guidance on case definitions, testing and resources including signage and consumer information

https://www.dhhs.vic.gov.au/novelcoronavirus

The Commonwealth Department of Health has updates on the national response to this health threat and provides resources to health professionals and consumers, including Coronavirus Health Information Line.

https://www.health.gov.au/health-topics/novel-coronavirus-2019-ncov

For information and guidance updated daily from WHO regarding the current outbreak of novel coronavirus (2019-nCoV)

https://www.who.int/emergencies/diseases/novel-coronavirus-2019

To assist HCW and researchers, The Lancet has created a Coronavirus Resource Centre to bring together content across Lancet journals as it is published.

https://www.thelancet.com/coronavirus

To assist HCW and researchers, New England Journal of Medicine has curated a collection of articles and other resources on 2019-nCoV 

https://www.nejm.org/coronavirus


February 2020 - Health outcomes attributable to CPE infections 

Carbapenemase-Producing Enterobacterales (CPE) are multi-drug resistant organisms that can a pose a potential public health threat; carbapenems are the most broad–spectrum β-lactam antibiotics active against gram-negative organisms where effectiveness is challenged by the global emergence of CPE.  Furthermore, the production of carbapenemase enzymes on mobile genetic elements increases the transmission potential of CPE. 

There have been multiple recently published systematic review and meta-analyses examining the health outcomes attributable to CPE infections.  Soontaros et al (Am J Inf C 2019; 47(10):1200-12) performed a systematic review of published studies assessing the association between CPE and death from 2012 to 2017, identifying 21 studies included in the meta-analysis.  CPE increased the risk of death by 273% (pooled OR 3.73, 95% CI 2.03-6.88); when adjusted for confounders such as age increased risk of death remained (OR 2.85, 95% CI 1.88-4.30).

Budhram et al (Inf C & Hosp Epi 2020; 41:37-43) performed a systematic review to identify studies from 2008 to 2018 that included a control group of patients with CPE infections. 17 studies met inclusion criteria; most were from Europe (68%). Mortality was the most commonly reported outcome (60%), followed by sequelae (including relapse, secondary BSI), antibiotic therapy (e.g. duration, appropriateness), and length of stay. None reported health-related quality of life outcomes.  Of studies that reported mortality outcomes, mortality rates ranged from 11.1 to 82.4%, with 76.3% of all deaths reported as in-patient including ICU deaths. A meta-analysis (n=5 studies) identified the risk of in-hospital death related to secondary bloodstream infection is increased four-fold in patients with CPE compared to those with a carbapenem-susceptible infection (ARD 0.25 [95% CI 0.17-0.32]).  

Both these studies suggest that the risk of death is significant amongst patients with infection or colonised with CPE infection and warrants strict infection control procedures.  Victoria has established guidelines on detection, reporting, identification and management of CPE colonised and infected patients in hospitals and residents in aged care facilities.  https://www2.health.vic.gov.au/about/publications/policiesandguidelines/carbapenemase-producing-enterobacteriaceae-guidelines. The DHHS also provides CPE reports, updated in 2020 to a new format, that are uploaded each quarter. https://www2.health.vic.gov.au/public-health/infectious-diseases/infectious-diseases-surveillance/interactive-infectious-disease-reports/cpe-surveillance-report

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December 2019 - Candida auris: an emerging multi-drug resistant organism associated with outbreaks in healthcare settings  

Candida auris (C. auris) is an emerging fungal pathogen: it is considered a potential public health threat to Victorian health services based on overseas experience where it has been associated with healthcare outbreaks. In contrast to other Candida species, C.auris can spread easily in healthcare settings causing nosocomial outbreaks and persist, both on the human host and on inanimate surfaces. It is a multidrug resistant organism, intrinsically resistant to fluconazole and with variable susceptibility to other important anti-fungal drug classes including amphotericin B and echinocandins.

Since 2009, it has been identified in over 30 countries and every continent except Antarctica however; it is thought to have been misidentified as C. haemulonii complex in the past. The first Australian detection of C. auris (South Africa clade) was in 2015 in WA with further detection since mid-2018 in Victoria, NSW and WA.  The Victorian guideline on Candida auris for health services1 was released in August 2019 (www2.health.vic.gov.au/infection-control) and the Australian Society for Infectious Diseases (ASID) has also published a position statement.2

The ASID statement2 reviews evidence regarding diagnosis, treatment and prevention and provides consensus recommendations for clinicians and microbiologists in Australia and New Zealand, which are summarised.

Epidemiology
Based on recent European data, bloodstream infections are the most frequently reported infections (18%), with infection at other sites (7%) and colonisations (75%).  Candidaemia is associated with high mortality rates (up to 30-60%). Most patients have had extensive healthcare exposure, with a median of 19 days from hospitalisation to acquisition.  Other identified risk factors include chronic illness, immunocompromised and presence of indwelling devices.  Colonisation of skin and mucosal surfaces often occurs in outbreaks and can reappear after apparent clearance.   Current Victorian recommendations1 advise that once a person is identified as a case of C. auris, they are considered potentially infectious indefinitely.

Screening
Patients should be screened using swabs of groin and axilla. 1,2 Additional sites can also be considered for screening to enhance yield (e.g. line exit sites, wounds).1,2 Data from colonised patients show that a single negative screen does not reliably exclude carriage.  Victorian guidelines1 advise one set of screening specimens is sufficient for patients screened based on overseas hospital stay in last 12-months or ward contacts of C. auris patient, whilst two sets separated by at least 24 hours is required for patients screened based on direct transfer from overseas hospital or room contact.

Lab testing
Culture-based (phenotypic) approaches are the mainstay of laboratory diagnosis of C. auris.  All yeast isolates should be identified to species level (e.g. “Candida albicans” not just “Candida spp.”) if from a sterile site or from a non-sterile site if screening based on risk (e.g. patient with overnight hospitalisation overseas).  Delays to results can occur as culture-based methods can require up to 10 days incubation to call a negative result; as well C. auris can be misidentified by conventional culture-based methods and require further work-up. 

MALDI-TOF MS used by some hospital laboratories can provide reliable identification using the appropriate database containing C. auris spectra representing all clades. In an outbreak setting, molecular techniques including whole genome sequencing is used for genotyping strains. 

Antifungal treatment
Use of an echinocandin is the current first-line recommendation for suspected/proven C. auris infections in adults. Antifungal susceptibilities for C. auris including MIC values should be interpreted with caution2 and formal Infectious Diseases consultation recommended1. Antifungal treatment of C. auris colonisation is generally not recommended. 

Infection control precautions
Isolation with standard and contact precautions. HCW caring for patients with C. auris should use ABHR when hands are not visibly soiled. If soiled, washing with soap and water recommended.2 Detergents and sporicidal disinfectants (e.g. ≥1000ppm bleach, peracetic acid, accelerated hydrogen peroxide) for environmental decontamination. Further information is provided in Victorian Guideline1 (Section 5 “Management and control of C. auris”).

Victorian health service response including local incident response and supporting roles of DHHS, VIDRL, MDU and VICNISS are outlined in detail in the Victorian guideline.1

References

  1. The Victorian guideline on Candida auris for health services (health.vic.gov.au/infection-control). Accessed November 11, 2019.
  2. Ong C, Chen S, Clark J, et al. Diagnosis, management and prevention of Candida auris in hospitals: Position statement of the Australian Society for Infectious Diseases (ASID). Int Med Jour. Published 2019. doi:10.1111/imj.14612.

October 2019 - Lessons from a Candida auris outbreak in England 

O’Connor et al. (J Hosp Infect 2019: 103; 106-111) describe their experience of an eight-week Candida auris outbreak on a vascular ward. Key learnings form their experience include the importance of early activation of a local incident management team supported by public health in screening and contact tracing. Of significance, isolates from two of the four cases demonstrated reduced susceptibility to echinocandins (first-line treatment for C. auris). As well, one bay contact with negative initial screening was positive when re-screened three-weeks later after transfer to another hospital.

Since its discovery in 2009, C. auris has been identified in more than 30 countries including Australia. In contrast to other Candida species, C. auris spreads easily in healthcare settings and has been associated with nosocomial outbreaks. The ability to persist in human hosts and inanimate surfaces, as well as the fact that this yeast is resistant to antifungal agents (resistance to fluconazole, variable susceptibility to other azoles, amphotericin and echinocandins), highlights the significance of this organism as a new nosocomial threat requiring enhanced infection control measures.

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October 2019 - Are ‘single room only’ hospitals effective in reducing healthcare-associated infections? 

A proposed strategy to reduce transmission of multi-drug resistant organisms is to accommodate patients in single rooms to reduce chance of transmission from other patients and improve compliance with infection control measures. Evidence to date linking hospital architectural design and prevention of healthcare-associated infection (HAI) is conflicting. McDonald et al. (JAMA Int Med August 2019) report a reduction in infections (VRE) and colonisations (VRE and MRSA) when a Canadian hospital moved to a new 350-bed facility in which all patients had single rooms. However, no differences were observed in Clostridioides difficile infections (CDI) or MRSA infections.

In this time-series analysis, the move was associated with immediate and sustained reductions over 3-years in the incidence of nosocomial VRE colonisation (from 766 to 209 colonisations, incident rate ratio 0.25; 95% CI 0.19-0.34). There was also a fall in MRSA colonisation (from 129 to 112 colonisations, IRR 0.57; 95% CI 0.33-0.96) and VRE infection (from 55 to 14 infections, IRR 0.30; 95% CI 0.12-0.75). However, no change in nosocomial CDI (236 to 223 infections, IRR 1.00; 95% CI 0.98-1.02) or MRSA infections (27 to 37 infections; IRR 1.02, 95% CI 0.97-1.07) was observed. The IRR estimates adjusted rates pre- and post-hospital move. For VRE colonisation (IRR = 0.25), the colonisation rate reduced by 75% post-move. For MRSA colonisation (IRR 0.57), colonisation rate reduced by 43% post-move.

Limitations of the study include being unable to control for other contemporaneous interventions in infection control and antimicrobial stewardship and no data on MDR Gram-negative organisms. As well, MRSA colonisation may have been acquired pre-admission. While reasons for no change in CDI rate were not clear, it is possible that CDI disease burden may be associated with additional factors, including antibiotic prescribing patterns prior to hospitalisation.   

This study adds observational evidence to support recommendations for single-room design in healthcare facility construction, in order to decrease risks of transmission of specific multidrug resistant organisms and healthcare–associated infections. However, there is on-going need to also optimise practices around use of antimicrobials, hand hygiene and facility cleaning.


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August 2019 - Prevalence of healthcare associated infections in Australian hospitals 

Russo and colleagues (Antimic Res & Inf Control 2019:8;114) undertook a point prevalence study in a sample of large acute care hospitals. The primary objectives were (1) to estimate the total prevalence of HAIs among adult inpatients in public acute care hospitals in Australia and (2) to describe the HAIs by site, patient factors, medical specialty and geographical location.

Hospitals were recruited by seeking an expression of interest. To maximise representation of large acute care public facilities, inclusion criteria included being in the AIHW Principal Referral or Group A hospitals peer grouping (i.e. hospitals with 24-hour emergency departments, ICU and specialised units including, but not limited to, oncology and coronary care). Exclusions included specialist and private hospitals. Patients were systemically sampled according to random allocation of each ward to odd or even bed numbers. Patients were excluded if <18 years, in emergency or admitted for same-day procedure. European Centre for Disease Prevention and Control HAI definitions were used. 

2,767 patients from 19 hospitals were included. The median age of patients was 67 years, and 52.9% of the sample were male. Presence of multi-drug resistant organisms was documented for 10.3% of the patients. There were 363 HAIs present in 273 patients. The prevalence of patients with a HAI was 9.9% (95%CI: 8.8–11.0) with individual hospital prevalence rates ranging from 5.7% (95%CI:2.9–11.0) to 17.0% (95%CI:10.7–26.1). The most common HAIs were surgical site infection, pneumonia and urinary tract infection, comprising 64% of all HAIs identified.  A peripheral intravascular device was present in 55.2% and an IDC in 20.7%.  Of 38 patients with a BSI, 35 (92.1%) had a vascular device in-situ. The most common organisms isolated were S. aureus (18.9%), E.coli or Klebsiella (24.3%), Enterococcus spp (13.5%), Candida spp (10.8%).  Of 66 of patients with a UTI, 33 (50%) an IDC in-situ. Risk adjustment was not undertaken and severity of illness was not reported. The authors note selection bias in this study to ensure jurisdictional representation and inclusion limited to large public hospitals.

Russo et al have undertaken the first HAI point prevalence survey to be conducted in Australia in 34 years concluding that regular, large-scale HAI surveys should be undertaken to generate national HAI data to inform and drive national interventions. These study results complement state-level and regional healthcare-associated infection surveillance program activities which incorporate continuous surveillance, point-prevalence surveys and periodic monitoring  to provide hospitals with ward-level data, risk adjustment, measures of severity of illness to assist with immediate responses and tailoring of prevention strategies.

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August 2019 - Effectiveness of peripheral intravenous catheter-related insertion and maintenance bundles 

Bundles improve staff compliance with best practice by simplifying guidelines into a short point-of-care reminders. CVAD insertion and maintenance bundles have been widely implemented and are recognised to reduce infection rates.  The success of the CVAD bundle in ICU patients can be attributed to standardisation of the bundle components and consistency in their application. Ray-Barruel and colleagues (Inf, Dis & Health 2019: 24; 152e168) have undertaken the first systematic review to examine the effects of bundles on PIVC insertion and maintenance on PIVC complications (pain, infiltration, extravasation, blockage, premature dislodgement, thrombosis, phlebitis) and PIVC-related BSI.

13 studies were included in this review where an insertion or maintenance bundle was defined a priori as including at least two evidence-based practices for insertion respectively.  All included studies reported implementing a PIVC care bundle for insertion (n= 9) or maintenance (n =10), or both (n =8) in an acute care hospital inpatient setting. Twenty-one different insertion bundle components were detailed in 10 studies. Each insertion bundle comprised two to seven items: the most often reported items were 2% chlorhexidine gluconate (CHG) skin prep, hand hygiene, vessel assessment/ site selection, aseptic technique, integrated closed catheter, and transparent film dressing.  Twenty-two different maintenance bundle components were identified in 11 studies. Each maintenance bundle comprised two to seven items: the most common maintenance bundle items included daily review of need for PIVC (n=7) and poster reminders of the bundle intervention (n=7).

There are fewer published RCTs in PIVCs than CVADs, and while CVAD bundles are generally based on components supported by RCT evidence, this is not the case for PIVC bundles.  The effect of PIVC care bundles on PIVC-related bloodstream infection rates appears promising but further research is needed to identify which bundle components are effective to support standardisation of bundle components. 

 

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June 2019 - Infection Control Literature Review 

Healthcare-associated, hospital-onset (HO) Clostridioides difficile infection is associated with both antibiotics and prolonged hospital stays.  C. difficile spores can survive on surfaces for up to five months, suggesting that hospital environments may play an important role in the spread of HO-CDI. There is little data on the role of intra-hospital transfers on transmission dynamics of HO-CDI.  

McHaney-Lindstorm (Jour Hosp Infect 2019; 102 (2): 168-169) and colleagues examined whether a higher number of intra-hospital patient transfers increases the risk of HO-CDI infection. This was a case-control study where the control group was selected by performing a 1:3 match based antibiotic use during hospitalization and age. 
In all, 386 cases of HO-CDI were identified during the 2-year study period. The case and control groups were well balanced for age, antibiotic usage and Charlson Comorbidity Index scores. Multivariate logistic regression analysis suggested a significant relationship between CDI risk and the number of transfers, where for each additional transfer, the odds of HO-CDI infection increased by ∼7% (OR: 1.07; 95% CI: 1.02–1.13). 
These results suggest that intra-hospital transfers expose patients to more environments that may harbour the C. difficile spores, putting patients who experience more intra-hospital transfers at greater risk of CDI. This supports the practice of reducing unnecessary patient movement within hospitals. 

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June 2019 - Transmission of Mobile Colistin Resistance (mcr-1) by Duodenoscope  

Infection control in endoscopy presents increasingly complex challenges. Since 2010, there have been several overseas outbreaks of CPE linked to the use of flexible endoscopes.  The Gastroenterological Society of Australia (GESA) and Gastroenterological Nurses College of Australia (GENCA) published the Infection Control in Endoscopy Guidelines (3rd edition, 2010) which are being updated this year.  In 2017, GESA, GENCA, ACIPC and Australasian Society of Infectious Diseases (ASID) developed consensus statements addressing this issue (J of Gastro and Hepatol 2019: 34:650-658). 
In this recent report (CID 2019: 68 (8); 1327–1334), transmission of mobile colistin resistance gene (mcr-1) was identified in two patients with highly-related K. pneumoniae clinical isolates.   An extensive field investigation, including screening targeted high-risk groups, evaluation of the duodenoscope, and genome sequencing of isolated organism, identified that a duodenoscope was the only common epidemiological link.  There were no identifiable breaches in reprocessing or infection control practices however evaluation of the scope identified intrusion of biomaterial under the sealed distal cap which was recalled.
Polymyxins such as colistin are used as a last-line antimicrobial treatment option for multi-drug resistant gram-negative infections. The spread of plasmid-mediated, mobile colistin resistance genes into carbapenamese-producing Enterobacteriacae raises the concern of potentially untreatable infections with significant transmission risks.   Instruments with complex tips (e.g. duodenoscopes and linear echoendoscopes) may transmit multidrug-resistant organisms persist despite recent initiatives to improve device safety. 


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April 2019- -Researching Effective Approaches to Cleaning in Hospitals (REACH) 

ACIPC 2018 delegates had the opportunity to hear investigators present interim findings from the REACH study which has now been published in Lancet Infectious Diseases (Mitchell B et al. Lancet Inf Dis 2019; epub 8/3/19). This is the first randomised controlled trial to investigate the effectiveness of a systematic bundle of interventions to improve environmental hygiene, targeting routine daily cleaning and terminal cleaning and disinfection in reducing health-care associated infections (HCAI) in hospitals.

The study was a stepped-wedge randomised controlled design, performed in 11 Australian hospitals between May 2016 and 2017. The intervention involved a review of the environmental hygiene approach in each hospital, and a structured, tailored set of recommendations to improve product choice, technique, audit, training, and communication of performance. The primary outcomes were incidences of health-care-associated S.aureus bacteraemia (SAB), C. difficile infection (CDI), and VRE infection. The secondary outcome was the thoroughness of cleaning of frequent touch points, assessed by a fluorescent marking gel. A unique aspect of the intervention was to raise the profile and importance of cleaning, support a culture shift in the perception and profile of environmental hygiene staff, and to encourage daily contact between environmental hygiene staff and ward leaders or managers. This is separately published (Mitchell B et al. Am J Inf Control 2018; 46(9):980-985).

Overall, there was a 37% reduction in VRE infections (from 0.35 to 0.22 per 10,000 occupied bed days (RR 0.63, 95% CI 0.41–0.97, p=0.0340), but no significant changes in the incidence of S. aureus bacteraemia (0.97 to 0.80/10,000 occupied bed days; RR 0.82, 95% CI 0.60–1.12, p=0.2180) or C. difficle infection (2.34 to 2.52/10,000 occupied bed days; RR 1.07, 95% CI 0.88–1.30, p=0.4655). The intervention increased the percentage of frequent touch points cleaned in bathrooms from 55% to 76% (odds ratio 2·07, 1·83–2·34, p<0·0001) and bedrooms from 64% to 86% (1·87, 1·68–2·09, p<0·0001). There were no noticeable changes in hand hygiene compliance or antimicrobial use during the study period.

This study underlines both the importance of environmental hygiene in preventing HCAI and also highlights our knowledge gaps around how what an effective environmental hygiene intervention looks like. The intervention was a mixture of training, education, organisational policy changes as required to increase the status of environmental hygiene and environmental hygiene staff. Any or all of these changes could have resulted in the reduction of VRE. It is unclear why there were no significant reductions in SAB and CDI: this could be further explored in the future by evaluating acquisition of colonisation rather than infection and looking also at the impact of appropriate use of a sporicidal disinfectant for C.difficile.

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April 2019 - Investigating Clostridium difficile Transmission Patterns between Infected and Colonised Patients Using Whole Genome Sequencing

Clostridium difficile is a leading cause of health-care associated infections, rivalling MRSA, accounting for $3.2 billion in excess costs annually globally. A recently updated ASID/ACIPC position statement on infection control for patients with CDI in Australian healthcare facilities was published (IDH 2019:24:32-43). Infection control recommendations for hospitals focus on preventing transmission from symptomatic CDI patients. Kong et al (CID 2019; 68 (1):204-209) undertook to investigate the relative roles of carrier and cases as a source of transmission to patients with CDI.

Investigators analysed patient movement data and performed whole genome sequencing (WGS) on 554 C. difficile isolates originally obtained during a NAP1 strain outbreak. Samples were collected from 353 colonised patients and 201 CDI cases for genetic testing.

Of CDI cases, 105 (52%) were genetically linked with 81 (77%) also having a plausible ward link. Of those with a likely source, 34/81 (42%) of linked cases were associated exclusively with a previous CDI case and 19/81 (23%) associated exclusively with an asymptomatic carrier.

This is the largest study to date investigating the roles of carriers and cases as sources of transmission. The use of WGS is currently considered the most discriminating typing/fingerprinting method and being increasingly adopted over other techniques such as pulsed-field gel electrophoresis (PFGE) or PCR ribotyping. This study confirms that colonised patients may be a source of onward transmission to incident CDI cases, but that spread from infected donors with diarrhoea is likely more frequent.

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