Methicillin-resistant Staphylococcus Aureus Nasal Carriage

This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms. For reprints contact: reprints@medknow.com How to cite this article: Thilakavathy P, Vijaykumar GS, Ramesh A, Janagond AB, Rajendran T, Jeremiah SS, Vithiya G. Methicillin-resistant Staphylococcus Aureus Nasal Carriage Among Health-care Workers: Decolonization and Follow-up Study Conducted in a Tertiary Care Hospital. J Hum Health 2015;1:16-9. Thilakavathy, et al.: MRSA Nasal Carriage Journal of Human Health ¦ Jan Apr 2015 ¦ Volume 1 ¦ Issue 1 17 Velammal Medical College Hospital and Research Institute. After obtaining ethical clearance, a total of 308 HCWs were enrolled in the study. The study group included doctors, nurses, midwives, technicians, patient care executives, and written informed consent was obtained from all HCW, who were included in the study. Nasal swabs were collected from each HCW. Sample collection Sterile cotton swabs were used for sample collection. The sample was obtained by rotating the swabs gently for fi ve times on both nares of the study participants so that the tip is entirely at the nasal ostium level, and it was transported to the laboratory. Bacterial isolates Of the 308 nasal swab samples, 48 were identified as S. aureus. The isolates from samples were identified and characterized using standard microbiological procedures. Swabs were plated on Mannitol Salt Agar (MSA) and incubated at 37°C. After overnight incubation, the plates were examined, and coagulase test (slide and tube) was performed. Those isolates that produced yellow colored colonies on MSA and coagulase positive were taken as S. aureus. The S. aureus isolates were subjected to antibiotic susceptibility test by Kirby-Bauer’s disk diffusion method on Mueller-Hinton (MH) agar and the zones were interpreted as per Clinical and Laboratory Standards Institute guidelines. [7] The following antibiotic disks were used cefoxitin (CXT 30 g), ciprofl oxacin (CIP 5 g), erythromycin (E 15 g), clindamycin (CD 15 g), pristniamycin (RP 15 g), teicoplanin (TEI 30 g), mupirocin (MU), and rifampicin (RF 5 g). Identifi cation of methicillin-resistant Staphylococcus aureus For the bacterial isolates that were confi rmed to be S. aureus, inoculums were prepared by making direct broth suspension of isolated colonies selected from 18 to 24 h agar plate. The suspension was adjusted to achieve a turbidity equivalent to 0.5 McFarland turbidity standard and inoculated on MH agar. Cefoxitin disk of strength 30 g was placed on the plates and incubated for 24 h at 35°C. Colonies with an inhibition zone 22 mm were read as MRSA (ATCC 25923) used as control strain. Methic i l l in-res is tant Staphylococcus aureus decolonization treatment For MRSA nasal carriers, mupirocin 2% ointment is advised to apply twice daily for 5 days. Postdecolonization screening for clearance Nasal swabs were obtained 1-week and 12 weeks after completing decolonization treatment to ensure clearance of the organism. [8] Statistical analysis The fi ndings were statistically analyzed Chi-square test (2) and P value (P < 0.05, statistical signifi cant).