Methicillin-resistant Staphylococcus aureus in geriatric patients: usefulness of screening in a chronic-care setting.

To evaluate the contribution of screening to the detection of cases of methicillin-resistant Staphylococcus aureus (MRSA) in a chronic-care facility. Surveillance and laboratory observational study. During a 7-month period, we compared imported and acquired MRSA in a chronic-care center by screening patients for carriage of MRSA on admission and discharge, and by recording all cases of clinical specimens positive for MRSA. The study was conducted in a 120-bed chronic-care center. This center admits approximately 850 patients per year. Approximately 90% of the patients were elderly and were admitted from other hospitals. Of 519 patients admitted during the study period, 129 were positive for MRSA at some point during their residence, including 60 (11.6%) with MRSA found within 48 hours of admission and 69 (13.3%; 53% of all positives) with nosocomial MRSA Of the 519 admissions, 332 (64%) were discharged, of whom 62 (19%) were positive for MRSA Of these 62, 43 (69%) acquired their MRSA during their stay in the center. Our study confirms the amplification effect of chronic-care facilities on MRSA propagation. It also shows that screening for MRSA carriage in a chronic-care center facilitates the early identification of a large proportion of patients with MRSA.