Bacterial contamination of hands and the environment in a microbiology laboratory

Summary This study investigated both the impact of glove usage on bacterial hand contamination of laboratory technicians and extent of environmental contamination of a microbiology laboratory with potential bacterial pathogens. Two groups of laboratory technologists participated in the study – one group who always used gloves when handling bacterial cultures and another group who did not. Semiquantitative bacterial sampling from technicians' hands was performed before and after a defined work period. Frequently touched areas of the laboratory were sampled over a four-week period and selective or chromogenic media utilised for the identification of meticillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa , Salmonella spp. and Enterobacteriaceae. Laboratory technicians who did not use gloves were at significantly greater risk of acquiring MRSA following their work periods but no protective effect was demonstrated for glove usage against acquisition of Enterobacteriaceae. Hand washing was equally effective at removing acquired bacterial pathogens in both groups of workers. Environmental sampling documented the presence of MRSA in one-fifth of sampled sites, with the most frequent recovery from computer keyboards. Enterobacteriaceae and P. aeruginosa were less commonly recovered from the environment. This study demonstrates that glove usage is protective against the acquisition of MRSA and that MRSA is the most frequently recovered bacterial pathogen from our microbiology laboratory environment.