Assessment of Gram- positive Bacterial Contamination on Stethoscopes inSome Hospitals in Khartoum State

Abstract

Stethoscopes are a potential factor for dissemination of bacteria from patient to another and thus recognized as critical public health problems. This study was conducted during the period from March to June 2014 to assess Gram positive bacterial contamination on stethoscopes. The stethoscope diaphragms were sampled by moistened cotton swab. The swabswere rotated over the internal and external surface of diaphragm. Each swab was soaked in 2 ml of sterile normal saline. The swabs were examined for bacterial load by Pour Plate Method. Gram-positive bacteria were identified by colonial morphology, Gram stain and biochemical tests. A total of 200 swabs were examined. Of these 179 (89.5%) were contaminated with bacteria. The range of bacterial load was 2x104-1126x104 cfu/diaphragm with average 210.2x104 cfu/diaphragm. The total number of Gram-positive bacteria was 140 isolates.These were coagulase-negative staphylococci84 (60%), followed by Bacillus species 43 (30.7%) and Staphylococcus aureus 13 (9.3%). It is concluded that the stethoscopes were highly contaminated. Potential pathogens were isolated.Stethoscope’s diaphragm cleaning and disinfecting before and after use are highly recommended. Further studies are required to validate the results of this study.