Molecular epidemiology of methicillin-resistant Staphylococcus aureus in 12 New York hospitals. MRSA Collaborative Study Group.

ABSTRACT

Consecutive single-patient methicillin-resistant Staphylococcus aureus (MRSA) isolates (270) from 12 hospitals (8217 beds) in metropolitan New York City were collected during May 1996. In 11 of 12 hospitals, MRSA was most frequent in the general medical services. DNA typing ("fingerprinting") revealed that mecATn554PFGE (pulsed-field gel electrophoresis) type IAA accounted for 113 (42%) of 270 isolates, was detected in all hospitals, and was the predominant clone in 9. Thirteen of 15 IEF isolates were from 1 hospital, and the remaining 2 were from another hospital of the same health system. Type VNHE was isolated from 22 (79%) of the 28 patients with AIDS, including 8 of 9 patients from an additional hospital. Subtype VNHE2 was recovered from 11 patients, 9 of whom had AIDS, including all 5 AIDS patients from one floor of a nursing home affiliated with a third hospital. By using both mecATn554 probes and PFGE, MRSA clusters and outbreaks may be detected and provide a rationale for appropriate infection control intervention.