Molecular characterization of Panton-Valentine leukocidin (PVL) toxin-encoding phages from South India.

A total of 19 methicillin-resistant Staphylococcus aureus (MRSA) isolates were investigated for Panton-Valentine leukocidin (PVL) toxin, PVL gene sequence variation and PVL-encoding phages. Whole genome sequencing was performed for all isolates. Analysis of MRSA isolates (n = 19) confirmed that most MRSA (n = 11) were positive for the PVL gene and were multidrug resistant. ST772-MRSA-V was the predominant PVL-positive MRSA clone, although all of them were found to carry the ΦIND772PVL phage in the genome. This study provides insights into the evolution of a new lineage of PVL-MRSA and highlights the potential risk of the emergence of multidrug-resistant community-acquired MRSA with high virulence.