Abstract :

Methicillin-resistant Staphylococcus aureus (MRSA) remains a significant global pathogen responsible for both healthcare-associated and community-associated infections. Historically, the presence of Panton–Valentine leukocidin (PVL) served as a key molecular marker distinguishing community-associated MRSA (CA-MRSA) from hospital-associated MRSA (HA-MRSA). However, increasing evidence of genetic convergence between these lineages challenges the reliability of PVL as a discriminating factor. Over time, the distinctions between community-associated (CA-MRSA) and hospital-associated (HA-MRSA) strains have become increasingly blurred. This is largely due to the ongoing exchange of genetic material, clonal expansion, and the dynamic nature of antibiotic resistance. In this review, we take a closer look at the molecular epidemiology of both CA-MRSA and HA-MRSA, with particular attention to the structure and pathogenic role of Panton–Valentine leukocidin (PVL). We also examine how the presence of PVL varies among different MRSA strains and discuss whether it still holds value as a marker in surveillance efforts. Given the rapid evolution of bacterial genomes, we reflect on the clinical implications of relying on PVL for classification. The review concludes by outlining future research priorities, especially the need for integrated genomic monitoring and more comprehensive typing strategies to enhance MRSA management and improve patient care.

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Keywords :

Staphylococcus aureus; PVL; CA-MRSA; HA-MRSA

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