Characterization of methicillin-resistant Staphylococcus aureus isolates from apparently healthy individuals in Malete, Kwara state, Nigeria

Abstract

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a common and continuously growing cause of nosocomial and community-acquired staphylococcal infections around the world. Screening for colonization with MRSA is a major aspect of control and limiting the spread of infections cause by this organism. We investigated the carriage of MRSA among apparently healthy individuals in four rural villages: Eleburu, Tapa, Atere and Apo all around semi-urban town-Malete, in Moro Local Government of Kwara State, Nigeria.
Methods: Nasal swabs were collected from volunteered individuals and were cultured on mannitol salt agar and blood agar for isolation and identification of Staph aureus using standard microbiological techniques. Susceptibility to cefoxitin disc (30 ag) was used to determine MRSA status of the isolates. Molecular method was used to detect the gene responsible for resistance among MRSA isolates. Antimicrobial susceptibility test to commonly prescribed antibiotics was carried out using discs diffusion method.
Results: Total number of individuals carrying Staph aureus in their nostrils was 42 (37.2 %). Antibiotics susceptibility profile of Staph aureus isolates showed 100 % resistance to cefuroxime, cefotaxime, cloxacillin and augmentin, and were 87 %, 81 %, 69 % and 23.8 % and 19 % resistant to tetracycline, ceftriaxone, erythromycin, ofloxacin and gentamicin respectively. A total of 6 (14%) Community –Acquired MRSA (CA-MRSA) isolates were recovered from individuals living in these villages. Molecular method detected muc and mecA genes in all the 6 (100%) CA-MRSA isolates and lukS-lukF was detected in 3 (50%) of the isolates.
Conclusion: Detection of CA-MRSA strains among these rural dweller indicates that they are harbouring enhance virulence organism that may manifest a more severe disease condition. The danger associated with high prevalence of multidrug resistant Staph aureus and CAMRSA; and its consequential effects of poor drug administration in Nigeria was discussed. There is need to establish a more strict legislation and enforcement on drug control; and a body that would monitor production and appropriate use of antibiotics in the Nigeria.

KEYWORDS: CA-MRSA, Staph aureus, Antibiotics, Rural Villages and Molecular Characterization