Literature Update - February/March 2010
Compiled by Dr Leon Worth, ID Physician
Prevention of Surgical Site Infections in Nasal Carriers of Staphylococcus aureus
Although nasal carriers of Staphylococcus aureus have increased risk for development of healthcare-associated infections, decolonisation by
intranasal application of mupirocin has not previously been shown to reduce surgical site infections. In a randomised placebo-controlled trial, Bode LGM
et al (N Engl J Med 2010; 362:9-17) investigated the utility of rapid diagnosis by means of a real-time polymerase-chain reaction (PCR) assay,
together with decolonisation using mupirocin nasal ointment and chlorhexidine soap.
Between October 2005 and June 2007, patients at 5 Dutch hospitals were screened for nasal carriage of S. aureus during the week before hospital
admission or immediately upon hospital admission. Microbiologic cultures from study patients were screened for 6 weeks after hospital discharge to identify the presence of
S. aureus infection.
In total, 6771 patients were screened (approximately 90% admitted to surgical hospital units), of whom 1251 were positive for S. aureus on PCR.
917 of these patients were randomised to receive placebo or treatment (mupirocin-chlorhexidine). Among patients who were randomised, 49 developed hospital-acquired
S. aureus infection: 17 (3.4%) in the mupirocin-chlorhexidine group and 32 (7.7%) in the placebo group (RR 0.42, 95% CI 0.23-0.75). Deep
surgical site infections were the most frequent infection, and these infections were significantly less frequent in the treatment group compared to the placebo group (RR 0.21).
Time to infection was significantly shorter in the placebo group than in the treatment group, and mean duration of hospitalisation was significantly shorter in the treatment
group compared to the placebo group (12.2 vs. 14.0 days, p = 0.04). In-hospital mortality did not differ between the 2 groups.
Results of this multicentre study indicate that a combined intervention consisting of rapid detection of S. aureus nasal carriage, together with
decolonisation of nasal and extra-nasal sites with mupirocin nasal ointment and chlorhexidine gluconate soap significantly reduces the risk of hospital-acquired
S. aureus infection. Unlike previous studies, benefits of this trial were likely to be associated with rapid detection (allowing targeted
decolonisation to be initiated within 24 hours of admission) and decontamination of extranasal sites (a potentially large bacterial load). Findings of this study may be
applicable to other centres, provided baseline prevalence of S. aureus colonisation is comparable to the Netherlands, and a similar low proportion
of methicillin-resistant S. aureus colonisation is evident. Resources required for the implementation of universal and intensive screening
strategies using PCR-based diagnostic methods must be explored.
High Uptake of HCW Influenza Vaccination using a Mandatory Vaccination Program
Influenza vaccination of healthcare workers has been associated with reduced morbidity and mortality, and is therefore recommended or endorsed by the Advisory Committee on
Immunization Practices in 1984, the Society for Healthcare Epidemiology, the Association for Professionals in Infection Control, and the Infectious Diseases Society of America.
However, many healthcare facilities have been unable to introduce a mandatory vaccination strategy, given controversy related to healthcare worker autonomy. In 2008, a large
US healthcare organisation (BJC HealthCare) introduced a mandatory influenza vaccination policy for all employees.
BJC HealthCare employs approximately 26000 healthcare workers, spanning acute services, extended care facilities, and ambulatory care. In 2008, influenza vaccination was
made a condition of employment for all BJC employees. The program was widely publicised, including a published letter by the CEO outlining the strategy. Free vaccine was
available. Vaccine delivery was tracked by entry into a database, and this allowed regular feedback (at least weekly) to managers. Medical or religious exemptions were
permitted, provided adequate documentation was received by the Human Resources department. The program commenced on 15 October 2008. Employees who were not vaccinated or
exempted from the program by 15 December 2008 were suspended without pay. Employees who were still not vaccinated by 15 January 2009 were terminated for failure to meet
their conditions of employment.
Of 25980 active employees, 25561 (98.4%) were vaccinated. Medical and religious exemption was granted to 321 (1.24%) and 90 (0.35%) employees, respectively. Therefore,
overall compliance with policy was 99.96%. Eight employees were terminated because of non-compliance with policy. Reasons for medical exemption included: egg allergy, prior
reaction to vaccine, history of Guillain-Barre syndrome. Possible adverse reactions were reported by 21 employees: sore arm (n = 11), allergic reaction (n = 5), possible vagal
response with fainting (n = 1).
This report provides an account of the successful implementation of a mandatory influenza vaccination program across a large healthcare organisation. The success of the campaign
may be related to communication, advanced tracking processes for real-time evaluation of vaccinated employees, and strong leadership support. Although the outcome suggests
that vaccination rates in excess of current Australian targets (e.g. >60%) are achievable, the longer term organisational impact upon cultural change and sustainability must
now be followed.