RESUMEN
OBJECTIVE: To study colonization with methicillin-resistant Staphylococcus aureus in a home care service during a 4-month period. DESIGN: Prospective study. SETTING: A home care service located in Rio de Janeiro, Brazil. PARTICIPANTS: Patients admitted to the home care service during this period, their household contacts, and health care workers (HCWs). METHODS: Swab specimens from the anterior nares were collected from each patient in the 3 groups at admission. Screening was repeated every 7 days. MRSA was detected using a mecA probe, and the clonality of isolates was evaluated by molecular methods, primarily pulsed-field gel electrophoresis. RESULTS: Of the 59 study patients, 9 (15.3%) had MRSA colonization detected; these cases of colonization were classified as imported. Only 1 (2.0%) of the 50 patients not colonized at admission became an MRSA carrier (this case of colonization was classified as autochthonous). Two (0.9%) of 224 household contacts and 16 (7.4%) of 217 HCWs had MRSA colonization. Cross-transmission from patient to HCW could be clearly demonstrated in 8 cases. The great majority of MRSA isolates belonged to the Brazilian epidemic clone. CONCLUSIONS: MRSA colonization was common in the home care service analyzed. The fact that the majority of MRSA isolates obtained were primarily of nosocomial origin (and belonged to the so-called Brazilian epidemic clone) substantiated our findings that all but 1 patient had already been colonized before admission to the home care service. Only cross-transmission from patients to healthcare workers could be verified. On the basis of these results, we believe that a control program built on admission screening of patients for detection of MRSA carriage could contribute to the overall quality of care.