Otoscope and stethoscope: Vehicles for microbial colonization at Tikur Anbessa Specialized Referral Hospital, Addis Ababa, Ethiopia

Abstract

Abstract
Background: In a hospital setting, medical equipment carried by health care workers such as otoscopes and stethoscopes may serve as harbors for microorganisms and may cause nosocomial infection.

Objective: This study was undertaken to determine microbial colonization of otoscopes and stethoscopes used by health care workers at Tikur Anbessa Specialized Referral Hospitals, Addis Ababa, Ethiopia.

Methods: A cross sectional study was conducted from November 2011 to April 2012. After obtaining verbal consent, a total of 130 stethoscopes and 6 otoscopes were swabbed by rubbing the diaphragm and bells of stethoscopes as well as handle and tips of otoscopes with sterile cotton tip applicator moistened in sterile saline. The swabbed sample was inoculated immediately on blood agar and Sabouraud dextrose agar for bacterial and fungal growth respectively.

Results: 136 (130 stethoscopes and 6 otoscopes) were swabbed for this study. The owners of the medical devices were nurses, general practitioners, resident medical doctors, interns and other healthcare workers from different departments. The overall microbial colonization from 136 medical devices sampled was found to be 82 (60.3%). About 111 microbial isolates were identified of which 94/111 (84.7%) were gram positive bacteria, 5/111 (4.5%) were gram negative bacteria and 12/111 (10.8%) were fungi (p<0.05). Staphylococcus aureus and coagulase negative Staphylococci isolates showed low level of resistance against most of the antibiotics tested.

Conclusion: Otoscopes and stethoscopes act as a vehicle for microbial colonization. Therefore, there is a need to evaluate efficacy of recommended cleaning practices in reducing the level of microbial colonization on these medical devices. [Ethiop. J. Health Dev. 2014;28(1):35-39]