Comparative Evaluation of MRSA Nasal Colonization Epidemiology in the Urban and Rural Secondary School Community of Kurdistan, Iraq

Background To study the nasal carriage rate of Staphylococcus aureus ( S . aureus ) (including methicillin-resistant strains) in secondary school community of the urban and rural districts of the Kurdistan region of Iraq, a cross-sectional population based survey was carried out in the city Duhok and rural areas of Amedya, Akre and Zakho. Methods Nasal swabs were obtained from nostrils of 509 students aged 14-23 years. Resistance to methicillin was assessed by Kirby-Bauer disk diffusion and agar dilution assay. Vancomycin sensitivity was also tested on Muller-Hinton agar. Results It was found that the frequency of overall S . aureus nasal carriage (SANC) was 17.75% (90/509, CI 95 , 14.58–21.42%). In urban areas, the carriage rate was 20.59% (49/239, CI 95 , 15.64–26.29%), whereas it was 15.24% (41/270, CI 95 , 11.17–20.10%) in rural districts. The frequency of methicillin-resistant S . aureus (MRSA) among the isolated strains was found to be 2.04% (1/49) and 21.95% (9/41) in urban and rural areas respectively. It was found that in urban residents, the odd ratio (OR) of acquiring SANC was 1.44 (CI 95 , 0.91-2.27%) and risk ratio (RR) was at least 1.35 (CI 95 , 0.92-1.96%) while OR decreased to 0.12 (CI 95 , 0.01-0.96%) for MRSA carriage. Hence, the S . aureus carriage rate was higher in urban districts compared to rural areas while more MRSA were found in rural areas compared to urban districts. All studied strains were sensitive to vancomycin. Conclusion This study provided baseline information for S . aureus nasal colonization in the region. Also, it showed that living in rural areas increased the odds of MRSA colonization. More attention should be paid to control MRSA colonization in rural communities.