Examination of Staphylococcus aureus Prophages Circulating in Egypt

infections are of growing concern given the increased incidence of antibiotic resistant strains. Egypt, like several other countries, has seen alarming increases in methicillin-resistant (MRSA) infections. This species can rapidly acquire genes associated with resistance, as well as virulence factors, through mobile genetic elements, including phages. Recently, we sequenced 56 genomes from Alexandria Main University Hospital in Alexandria, Egypt, complementing 17 genomes publicly available from other sites in Egypt. In the current study, we found that the majority (73.6%) of these strains contain intact prophages, including Biseptimaviruses, Phietaviruses, and Triaviruses. Further investigation of these prophages revealed evidence of horizontal exchange of the integrase for two of the prophages. These Egyptian prophages are predicted to encode numerous virulence factors, including genes associated with immune evasion and toxins, including the Panton-Valentine leukocidin (PVL)-associated genes -PV/ -PV. Thus, prophages are likely to be a major contributor to the virulence of strains in circulation in Egypt.