Epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in a university medical center day care facility

BACKGROUND: Few data are available on MRSA colonization in day care. We performed a study in a medical university child care center to determine the epidemiology of MRSA in this population. \r\n\r\nMETHODS: A cross sectional study was done involving 104 day care attendees and 32 adult employees. Swab samples were taken from children, employees, the environment, and household contacts of participants found to be colonized with MRSA. Parents and employees completed questionnaires. Swabs were incubated in broth, then plated on agar and identified as MRSA by routine methods. Isolates were analyzed for relatedness using molecular typing. Statistical analysis was performed. \r\n\r\nRESULTS: The prevalence of MRSA in the children was 6.73%. One employee (3.13%) was colonized with MRSA. Cultures of 6 of 17 (35.3%) family members of participants positive for MRSA yielded MRSA. MRSA was recovered from 4 environmental samples. On molecular typing, many of the MRSA isolates were indistinguishable. Univariate analysis identified macrolide antibiotics (p=0.004), asthma medications (p=0.036), other medications (p=0.036), and previous surgery (p=0.022) as risk factors. On multivariable analysis, receipt of macrolide antibiotics (p=0.002; OR 39.6; 95% CI 3.4-651.4), and receipt of asthma medications (p=0.024; OR 26.9; 95% CI 1.5-500.7) remained related to MRSA colonization. \r\n\r\nCONCLUSIONS: There was a low prevalence of MRSA colonization in children and employees in the child care center. A higher prevalence of colonization was found among household contacts of children and employees colonized with MRSA. Molecular typing showed that transmission of MRSA likely occurred in the child care center. Macrolide antibiotics may increase the risk of MRSA colonization in this population.\r\n