A community based Study on Nasal Carriage of Staphylococcus aureus

Abstract

Background. Staphylococcus aureus is a major bacterial cause of superficial infectionand a health care associated infection. The emergence of multiple resistances to anti staphylococcal penicillins like cloxacillin, methicillin and other agents has compromised therapy. Methicillin Resistant Staphylococcus aureus (MRSA) infection has become a major problem among the hospitals and the communities. Community studiesin MRSA colonization are lacking. The aim of this study was to describe the prevalence of Methicillin Sensitive Staphylococcus aureus (MSSA) and MRSA nasal colonization in the community and antibiotic susceptibility patterns of these isolates. Methods. This study was a community based descriptive cross sectional study. Nasal samples for S.aureus culture and sociodemographic data were obtained from 317 adults and children?2 years of age from the selectedtwo communities over a period of two months. S. aureus isolates were identified by routine laboratory methods and antimicrobial susceptibility tests were done by following the CLSI guidelines. Results. Of the 317 persons, 88(27.76%) were positive for S. aureus. Of the 88 isolates, 18 were MRSA and 70 were MSSA. Of the MRSA isolates the sensitivity to Erythromycin, Clindamycin, Linezolid, Ciprofloxacin, Trimethoprim- sulfamethoxazole, Tetracycline and Gentamicin were 5.55%, 33.33%, 100%, 94.44%, 94.44%, 77.77%, 94.44% respectively. Of the MSSA isolates the sensitivity to Erythromycin, Clindamycin, Cefoxitin, Linezolid, Ciprofloxacin, Trimethoprim- sulfamethoxazole, Tetracycline and Gentamicin were 44.28%, 78.57%, 100%, 100%, 72.85%, 95.71%, 84.28%, 81.42% respectively. Inducible Clindamycin resistance was reported 44.44%, 7.14% for MRSA and MSSA isolates respectively. Conclusion. More than a quarter of the study population were colonized with S. aureus. MRSA colonization prevalence was 5.67% (18/317). More than 75% MRSA isolates were sensitive to Ciprofloxacin, Gentamicin, Trimethoprim ≥ sulfamethoxazole, Tetracycline, Linezolid. Therefore, MRSA isolates of this study were more likely to be community acquired. However, further molecular studies are needed to confirm these findings.