Towards Understanding the Clonality of Methicillin Resistant Staphylococcus Aureus in Sokoto State Nigeria

Introduction: The epidemiology of MRSA strains is constantly changing and the potential utility of genomic surveillance in defining its population structure and outbreaks of possible high-risk lineages in Sokoto state cannot be overstated. This study brings to light the various clones, spa-types, sequence types (ST) and the resultant clonal complexes (CC) of MRSA strains in Sokoto state as a step towards an all-inclusive MRSA surveillance system. Methods: Phenotypic determination of the presence of MRSA was carried out by subjecting the isolates to Oxacillin resistance screening agar base test (ORSAB). The PCR products (mecA and spa) where electrophoresed on ۱.۵% agarose gel and the spa positive isolates were sequenced and analyzed. Based upon repeat pattern (BURP) algorithm was used to compute spa clonal complexes (spa-CCs) Results: In this study, analysis of ۱۶ MRSA strains revealed ۱۰ different spa-types, varying in length between ۱ (t۲۶۷, t۰۲۱), ۲ (t۰۴۴, t۱۲۷) and ۴ (t۱۸۳۹, t۲۰۲) repeats, which were clustered into ۲ different groups and ۲ singletons. The MLST mapping of the spa types of ۱۶ MRSA isolates revealed seven different sequence types (ST-۱, ST-۹, ST-۵۵, ST-۹۳, ST-۹۷, ST-۸۰ and ST-۴۶۳) clustered into spa-CC ۰۷and spa-CC ۰۰۳. Conclusion: The present study provides an understanding of the MRSA clonal population in Sokoto, revealing the ۱۰ different spa-types in circulation and providing awareness of the proliferation of spa-types t۰۹۱ and t۰۴۴. Genetic Surveillance for these clones needs to be coordinated nationally and locally because successful clones are not confined by state or country boundaries.

Keywords:

Spa-Types , Clonal Complexes , Sequence Types , MRSA , Sokoto