Prevalence, Antimicrobial Resistance Profiles, and Molecular Characteristics of Methicillin-Resistant Staphylococcus aureus Among School Children in Nha Trang, Central Vietnam

<i>Staphylococcus aureus</i> (<i>S. aureus</i>), especially Methicillin-resistant <i>Staphylococcus aureus</i> (MRSA), remains a major public health concern both in hospital and community settings. The MRSA carriage situation among schoolchildren in Vietnam is limited. A cross-sectional study was conducted in March 2023 to assess the prevalence, antimicrobial resistance patterns, and molecular characteristics of MRSA among schoolchildren in Nha Trang, Vietnam. Schoolchildren from grades 1 to 12 (ages 6-18 yrs) were enrolled. Background epidemiological data and nasal swabs were collected. Nasal samples were processed at the Pasteur Institute in Nha Trang, Vietnam, for <i>S. aureus</i> culture. Out of 1210 participants enrolled, <i>S. aureus</i> prevalence was 18.3% (222/1210), of which 41% (91/222) were MRSA. Primary school children showed the highest prevalence of MRSA colonization (48%), 32.8% in secondary, and 27.8% in high school. Among MRSA isolates, high levels of resistance were detected against trimethoprim-sulfamethoxazole (100%), erythromycin (68.2%) and clindamycin (45.1%). Multidrug resistance (MDR) occurred in 30% (27/90) of MRSA isolates. <i>Staphylococcal</i> cassette chromosome <i>mec</i> (SCC<i>mec)</i> subtype IVa was dominant (66.0%), followed by type IV (7.0%) and type V (6.0%). MLST data revealed genetic diversity whereby ST45 dominated, followed by ST546 and ST188. Continuous MRSA surveillance is essential to monitor emerging strains in the communities.