Literature Update - December, 2003
Compiled by Dr Deb Friedman, VICNISS ID Physician
Bacterial Colonisation of Stethoscopes
There is literature available about the organisms that colonise the bell and diaphragm components of stethoscopes, and
about how to reduce such contamination by cleaning with propyl alcohol.
A group from London (Journal of Hospital Infection, 2003; 55(3):236-8.) investigated the organisms that can be found
on the earpieces of stethoscopes, in order to clarify if they represent a source of cross-infection. They sampled 38
ward stethoscopes, and 36 doctors' stethoscopes, and found that 66% of the ward instruments, and 69% of the privately
owned equipment were colonised with bacteria at the bell/diaphragm or earpiece.
The organisms cultured included bacteria and fungi. The commonest bacteria were coagulase-negative Staphylococci
and gram-negative bacilli, although MRSA was detected from 1 earpiece.
Although cleaning of the bell/diaphragm reduced colonisation, it did not reduce levels on the earpieces.
This may be due to the difficulty involved in cleaning the earpiece orifice, and presents a problem for staff
who may acquire ear infections by sharing stethoscopes.
The organisms cultured from the bell/diaphragm and earpieces indicate the importance of regularly cleaning stethoscopes.
Bacterial Contamination Associated with Paper-Towel Dispensing
A group from Wales (Am J Infection Control 2003;31(7):387-91) has studied whether or not bacterial transfer can occur
from paper-towel dispensers. They found that this transfer occurs in 2 directions: from contaminated hands to
dispenser exits, and from contaminated exits to clean hands. The latter mode of transfer was approximately ten
times more common in this study, and appeared to occur when freeing jammed towels.
This study has some important implications. While staff members may believe that they are actively cleaning
their hands to prevent the transmission of infection, they may inadvertently contaminate their hands with organisms
that could cause disease.
This highlights the fact that alcohol-based hand rubs, which do not require hand drying are a safe and effective
method for cleaning hands within hospitals.
Infection Control Programs Can Reduce Bloodstream Infection (BSI) Rates
It was demonstrated long ago that infection control programs have a very positive effect on nosocomial infection
rates. A group from Argentina (Am J Infect Control, 2003;31(7): 405-9) instituted an infection control program in
their intensive care unit, using education and performance feedback, and studied their device-associated BSI rates.
Overall rates of catheter-related BSI decreased markedly because of the education and performance feedback
programs. In addition, they noted an improvement in catheter-site care during the study period.
This paper should give all infection control practitioners renewed enthusiasm. It really is possible to reduce
nosocomial infection rates by educating staff and giving them feedback about their performance.
MERRY CHRISTMAS AND HAPPY NEW YEAR!