Carriage of methicillin-resistant Staphylococcus aureus in children in Brazil

Abstract The extent of methicillin-resistant Staphylococcus aureus (MRSA) carriage in Brazilian infants is largely unknown. We evaluated the presence of MRSA nasopharyngeal (NP) carriage in 686 children younger than 5 years with respiratory tract infection (609) and meningitis (77). S. aureus was isolated in 93 (13.5%) NP specimens of which 7 (1.02%) were identified as MRSA (oxacillin MIC, >256 μg/mL) harboring SCC mec type III. The dendrogram derived from the pulsed-field gel electrophoresis gel images showed that the MRSA strains diverged from the Brazilian endemic hospital-acquired clones from 10.4% to 21.7%. Although the MRSA strains were recovered from children within the first 6 h of their admission to hospital, the presence of SCC mec type III along with the multidrug-resistant profile of the isolates raises the hypotheses that these MRSA strains may have hospital origin and are now spreading into the pediatric community as colonizing pathogens.