Detection of diverse genotypes of Methicillin-resistant Staphylococcus aureus from hospital personnel and the environment in Armenia

Hermine V. Mkrtchyan, Zhen Xu, Maria Yacoub, Mary M. Ter-Stepanyan, Hayk D. Karapetyan, Angela M. Kearns, Ronald R. Cutler, Bruno Pichon, Armen Dz Hambardzumyan

Methicillin-resistant Staphylococcus aureus (MRSA) is a public health concern internationally. Studies examining a range of cohorts have been reported from various regions of the world, but little is known about the molecular epidemiology of MRSA in Armenia. Between May and September 2013, twenty isolates of methicillin-resistant Staphylococcus aureus (MRSA; mecA positive) were recovered from hospital personnel (n = 10; 9 females, 1 male) and environmental sites (n = 10) in the maternity ward of one of the teaching hospitals in Armenia. Multi-locus sequence type clonal complex (MLST-CC) assignments inferred from spa typing data revealed the majority belonged to 3 pandemic lineages of MRSA including: t008-CC8-SCCmecV (n = 10; 7 from personnel); t021-CC30-SCCmecIV (n = 5; all environmental); and t1523-CC45 (n = 2; 1 from personnel), one harboured SCCmecV the other was SCCmec non-typable. The remainder identified as belonging to genotype t364-CC182, both of which harboured a novel SCCmec cassette with kdp, rif5, ccrB2 and ccrC detected by PCR (both from personnel); and t325-CC88-SCCmecIV (n = 1; environmental). All MRSA were negative for the Panton-Valentine Leukocidin (PVL) locus and three CC8 strains were positive for the arginine catabolic element (ACME). In this small study, we report for the first time of the occurrence of diverse MRSA genotypes belonging to both pandemic and more sporadic international clones in Armenia harbouring the smaller SCCmec types and/or ACME, both of which have been associated with strain fitness. Further surveillance is warranted to better understand the prevalence, clinical and molecular epidemiology of MRSA throughout Armenia.