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A quasi-experimental study on stethoscopes contamination with multidrug-resistant bacteria: Its role as a vehicle of
Raeseok Lee1, Su-Mi Choi1,2, Sung Jin Jo3
1Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
Abstract:
Stethoscopes have been suggested to be a possible vector of contact transmission. However, only a few studies have focused on the prevalence of contamination by multidrug-resistant (MDR) bacteria and effectiveness of disinfection training to reduce. This study is to investigate the burden of stethoscope contamination with nosocomial pathogens and multidrug-resistant (MDR) bacteria and to analyze habit changes in disinfection of stethoscopes among healthcare workers (HCWs) before and after education and training. We performed a prospective pre and post quasi-experimental study. A total of 100 HCWs (55 doctors and 45 nurses) were recruited. HCWs were surveyed on their disinfection behavior and stethoscopes were cultured by pressing the diaphragm directly onto a blood agar plate before and after education on disinfection. Pulsed-field gel electrophoresis was performed to determine the relatedness of carbapenem-resistant Enterobacteriaceae. Most of the stethoscopes were contaminated with microorganisms before and after the intervention (97.9% and 91.5%, respectively). The contamination rate of stethoscopes with nosocomial pathogens before and after education was 20.8% and 19.2%, respectively. Stethoscope disinfection habits improved (55.1% vs 31.0%; p<0.001), and the overall bacterial loads of contamination were reduced (median colony-forming units, 15 vs 10; p = 0.019) after the intervention. However, the contamination rate by nosocomial pathogens and MDR bacteria did not decrease significantly. A carbapenemase-producing Klebsiella pneumoniae isolates from a stethoscope was closely related to isolates from the patients admitted at the same ward where the stethoscope was used. Stethoscopes were contaminated with various nosocomial pathogens including MDR bacteria and might act as a vehicle of MDR bacteria. Continuous, consistent education and training should be provided to HCWs using multifaceted approach to reduce the nosocomial transmission via stethoscopes.
Insights
Stethoscopes frequently harbor nosocomial pathogens and multidrug-resistant (MDR) bacteria. While improved disinfection habits were observed, targeted education is crucial to significantly reduce contamination rates and prevent healthcare-associated infections.
Area of Science:
- Infection Control
- Microbiology
- Healthcare Epidemiology
Background:
- Stethoscopes are essential diagnostic tools but can transmit healthcare-associated pathogens.
- Limited data exists on multidrug-resistant (MDR) bacteria contamination on stethoscopes and the impact of disinfection training.
Purpose of the Study:
- To assess stethoscope contamination with nosocomial pathogens and MDR bacteria.
- To evaluate changes in healthcare workers' (HCWs) stethoscope disinfection habits post-education.
- To analyze the effectiveness of disinfection training on reducing bacterial contamination.
Main Methods:
- Prospective pre- and post-intervention quasi-experimental study.
- Survey of 100 HCWs on disinfection behaviors.
- Stethoscope cultures before and after educational intervention.
- Pulsed-field gel electrophoresis for carbapenem-resistant Enterobacteriaceae relatedness.
Main Results:
- High rates of stethoscope contamination persisted post-intervention (91.5%).
- Nosocomial pathogen contamination rates showed no significant decrease (20.8% vs 19.2%).
- Stethoscope disinfection habits improved significantly (55.1% vs 31.0%), and overall bacterial load reduced (median CFU: 15 vs 10).
Conclusions:
- Stethoscopes are consistently contaminated with nosocomial pathogens, including MDR bacteria, posing a transmission risk.
- While disinfection habits improved, contamination rates by specific pathogens did not significantly decrease.
- Continuous, multifaceted education is essential for HCWs to mitigate nosocomial transmission via stethoscopes.
