The majority of MRSA colonized children not given eradication treatment are still colonized one year later. Systemic antibiotics improve the eradication rate

<p><b>Background:</b> Colonization with methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) can cause endogenously derived infections and be a source of transmission to other people. Neither colonization time of asymptomatic MRSA colonization nor the effect of treatment aiming at MRSA eradication in children has been thoroughly investigated.</p> <p><b>Methods:</b> Two hundred ninety-three children <18 years in the mandatory follow-up program for MRSA-carriers in Malmö, Sweden were evaluated. Samples from the throat, nares, perineum and skin lesions from each child were screened for MRSA with a PCR-based broth enrichment method. PVL presence and <i>spa</i>-type were evaluated in a majority of cases. The sampling was repeated approximately every 6 month after initial detection. When three consecutive sets of negative samples during at least a 6-month period were obtained, the MRSA was considered permanently eradicated. MRSA eradication treatment given, on clinical grounds during follow-up, was noted.</p> <p><b>Results:</b> One year after detection 62% of the untreated children were still MRSA positive and after 2 years 28%. MRSA throat colonization and having MRSA positive household contacts significantly prolonged the observed colonization time. Topical MRSA eradication treatment was successful in 36% of cases and in 65% if systemic antibiotics were added. Presence of PVL correlated with shorter observed colonization time in the older age group and with increased eradication success among throat carriers.</p> <p><b>Conclusion:</b> MRSA throat colonization and having MRSA positive household contacts prolongs the time of MRSA colonization in children. Systemic antibiotics enhance the effect of MRSA eradication treatment.</p>