Evidence of transmission of a Panton-Valentine leukocidin-positive community-acquired methicillin-resistant Staphylococcus aureus clone: a family affair.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) may represent a serious public health problem, owing to the spread of toxin-producing lineages. The presence of genes encoding for Panton-Valentine leukocidin (PVL) is an important virulence marker, as the clinical sequelae of PVL-positive infections are often described as more severe than those of PVL-negative S. aureus infections. To date, the presence of PVL has not appeared to be common in Italy; we describe the intrafamilial transmission of an epidemic PVL-producing CA-MRSA lineage, Southwest Pacific clone (SWP). Our data suggested that the strain circulated from the father, who was recurrently affected by a soft tissue infection, to the mother, who showed nasal colonization, and to their child, who was hospitalized with symptoms of necrotizing pneumonia. In this case, we found that a recurrent skin infection that is not normally taken into account may represent a serious threat if caused by a PVL-producing strain. Our findings may have considerable implications for strategies for infection control and treatment of methicillin-resistant S. aureus infections.