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

Staphylococcus aureus (S. aureus), especially Methicillin-resistant Staphylococcus aureus (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 S. aureus culture. Out of 1210 participants enrolled, S. aureus 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. Staphylococcal cassette chromosome mec (SCCmec) 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.