Abstract:
Staphylococcus aureus is found on most surfaces especially in public areas like hospitals
and schools and on frequently touched areas like toilet and class room door handles.
Methicillin resistant S. aureus (MRSA) is a strain of S. aureus which is resistant to
methicillin. There are two types of MRSA; Community acquired methicillin resistant S.
aureus (CA-MRSA) and hospital acquired methicillin resistant S. aureus (HA-MRSA).
MRSA in the community presents a significant reservoir that could enter into healthcare
facilities and spread among patients and also is a health risk for immunosuppressed
populations in the community. The study aimed at determining the prevalence of MRSA
isolated from toilet and classroom door handles as a potential source of infection to the
students and the workers in selected schools in Nairobi, Kenya. The study also compared
the prevalence of MRSA between day and boarding girls, boys and mixed secondary
schools. Twelve secondary schools in Nairobi County were randomly selected and 306
samples from both the toilet and classroom door handles were collected using sterile
swabs and transported to the National microbiology reference laboratory (NMRL) at the
National Public Health Laboratories (NPHL) for Staphylococcus isolation. Sample
collection was done over a duration of one month. Isolation of S. aureus was done by
use of selective media Mannitol salt agar, antibiotic susceptibility of MRSA isolates was
done by disk diffusion method and Polymerase chain reaction (PCR) was used to detect
genes for methicillin resistance MecA and PVL genes. The prevalence of S. aureus was
20% and 19.6% of the S. aureus isolated were MRSA positive by both antimicrobial
susceptibility test (AST) and PCR detection. MRSA in this study was only found in
girls’ schools and mixed schools and none in the boys’ schools. Twenty percent of S.
aureus showed the presence of Pantone Valentine Leukocidin (PVL) virulence genes
while 8% showed the presence of both genes. Fifty six percent of isolates which
contained mecA gene had also PVL genes. The presence of both genes in this study
indicates that surveillance and researches on MRSA that carry both PVL and mecA gene
should continue to provide a significant insight into the prevalence and epidemiology of
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these important resistant pathogens. The findings also emphasise the need to formulate
hygiene measure in the schools including hand washing and disinfecting of all services
that could act as a source of infections on MRSA. This could prevent possible spread of
MRSA and other related pathogens to students and workers in the schools especially the
food handlers in the school’s kitchen and the community