Bacterial contamination of laptop computer keyboards used by students of COVAB and CHS, Makerere University

Abstract

Laptops computers are ubiquitous in the school setting and have been shown to be contaminated with potentially pathogenic and skin microorganisms. This study was carried out to determine the bacterial contamination of laptop computer keyboards used by students at Makerere University. Samples were collected from laptop keyboards from two different colleges i.e. College of Veterinary Medicine, Animal resources and Biosecurity and College of Health Sciences. A total of 80 samples were collected from computer keyboards (40 from each college). The collected samples were inoculated onto XLD agar, MacConkey agar and mannitol salt agar by following standard methods. The isolates obtained were examined and identified by colonial morphology, Gram reaction and biochemical characteristics. All (100%)S sampled laptops had growth of at least 1 or more microorganisms on culturing. Majority of keyboards sampled, tested positive for skin organisms, which included Staphylococcus aureus (77.5%) and Escherichia coli (36.3%). They also tested positive for pathogenic bacteria which included Salmonella spp (28.8%) and Pseudomonas aeruginosa (20%). Samples from COVAB had E. coli (52.5%), S. aureus (70%), Salmonella (32.5%), Pseudomonas (17.5%), and more than a third (35%) of the samples had both E. coli and S. aureus. Samples from CHS had E. coli (20%), S. aureus (85%), Salmonella (25%), Pseudomonas (22.5%), and less than quarter (17.5%) samples had both E. coli and S. aureus. However, the prevalence of E. coli was significantly (P=0.02) higher at COVAB compared to CHS. The study showed that microbial contamination of keyboards is prevalent and therefore, keyboards must always be decontaminated with disinfectants daily or when visibly soiled to reduce on chances of being infected.