Methicillin-Susceptible Staphylococcus aureus ST398, New York and New Jersey, USA

Borges AS, et al. Araçatuba virus: a vac-cinialike virus associated with infection in humans and cattle. from humans and cattle in Rio de Ja-neiro State: Cantagalo virus may derive from Brazilian smallpox vaccine. Virol-Ferreira F, et al. Natural human infections with vaccinia virus during bovine vaccinia outbreaks.proved assay to detect neutralizing-anti-body following vaccination with diluted or undiluted vaccinia (Dryvax) vaccine. al. Nested-multiplex PCR detection of Orthopoxvirus and Parapoxvirus directly from exanthematic clinical samples. et al. Real-time PCR assay to identify variants of Vaccinia virus: implications for the diagnosis of bovine vaccinia in Brazil. To the Editor: Clinical infections with livestock-associated Staphylococcus aureus sequence type (ST) 398 have been reported in Europe, Canada, and the People's Republic of China (1), as well as the Caribbean (2,3), and Colombia (4). Most reports describe infection with methicillin-resistant S. aureus; relatively few describe infection with methicillin-susceptible S. aureus (MSSA). In the United States, colonization of healthy adults by ST398 has been reported in Iowa (5) and in New York, New York (2); MSSA infections have been anecdotally reported in St. Louis, Missouri (6), and The Bronx, New York (7). We describe 8 infections with MSSA ST398 in the New York City area during a 7-year period (2004– 2010). Five infections with a related ST (ST291) from clonal complex (CC) 398 also were identifi ed. These fi ndings highlight the emergence of clinical infections with 2 distinct CC398 sequence types in the New York City area. Retrospective typing of 4,167 clinical S. aureus isolates from various studies involving inpatients and outpatients in the New York City area identifi ed 13 mecA-negative isolates with CC398-associated spa types (Table). Nine isolates were obtained from cultures of outpatients with skin and soft tissue infections; samples were submitted by physicians in the community. One isolate was associated with recurring skin and soft tissue infections in multiple body sites (BK21466); another was associated with genital infection (BK21732). Of the 4 ST398 isolates derived from bloodstream infections in hospitalized patients, 3 were recovered from intravenous drug users, 1 of whom died 1 day after admission for variceal bleeding (BK26722). Unlike the multidrug-resistant ST398 MSSA recently described in Colombia (4), most isolates in this study were susceptible to all antimicrobial drugs tested except penicillin, although several strains exhibited resistance to clindamycin and erythromycin. One isolate (BK23527) was submitted as oxacillin resistant (MIC ≈4 μg/mL) but lacked the mecA gene, which suggested that …