Survey of methicillin-resistant Staphylococcus aureus among students in the Faculty of Associated Medical Sciences, Khon Kaen University

Abstract

Staphylococcus aureus is an important etiology of both hospital- and community-acquired infections because the carriers with this organism can transferred to other persons. Infection caused by S. aureus becomes a difficult treatment because it is usually multidrug-resistant, especially methicillin-resistant S. aureus strains (MRSA). This study aimed to investigate MRSA carriers among students in Faculty of Associated Medical Sciences of Khon Kaen University between January and October 2014. The study plan was clarified, and all volunteers signed a consent form before collecting samples by swabbed from the anterior nares.  A total of 212 students were included. The samples were enriched overnight in tryptic soy broth with 5% NaCl before subcultured on mannitol salt agar (MSA) and the organisms were then identified as S. aureus by Gram staining, catalase, coagulase and mannitol fermentation test. The S. aureus isolates were further tested for antimicrobial susceptibility to 7 agents included cefoxitin, clindamycin, erythromycin, vancomycin, tetracycline, penicillin and ofloxacin by using standard disk diffusion method. Of the 212 samples, 43 methicillin-susceptible S. aureus (MSSA) strains (20.3%) were isolated. Most of them (88.4%) were resistant to penicillin and all penicillin-resistant isolates produced ß-lactamase. In conclusion, MRSA carriers were not found among students in Faculty of Associated Medical Sciences of Khon Kaen University.