Nasal Colonization by Methicillin and Glycopeptide Resistant Staphylococcus aureus in Symptomatic and Asymptomatic Individuals in Maputo, Mozambique

Background and aim: Staphylococcus aureus nasal carriage is an important source of community- and hospital-associated infections, including methicillin-resistant strains (MRSA). Detecting MRSA colonization is essential for infection prevention and may help guide antimicrobial therapy. This study aimed to determine the prevalence of nasal colonization by S. aureus and assess methicillin and glycopeptide resistance patterns in hospital and non-hospital settings in Maputo, Mozambique. Methods: This is a cross-sectional study was conducted among symptomatic outpatients and asymptomatic university students. Nasal specimens were cultured on Mannitol Salt and HiCrome™ Rapid MRSA agar, with isolates identified by Gram stain, catalase, and Microgen® Staph tests. Antimicrobial susceptibility to cefoxitin, vancomycin, and teicoplanin was assessed using the Kirby-Bauer method. Results: A total of 50 (39.1%) S. aureus isolates were obtained from 128 collected nasal samples, in which 104 (31.3%) were from university students and 24 (7.8%) from outpatient’s form university clinic. The isolates showed a low overall 7.8% resistance to cefoxitin and, 14.1% and 11.7% presumptive resistance to teicoplanin and vancomycin, respectively. Conclusion: Methicillin and glycopeptide resistant S. aureus were highly prevalent in asymptomatic students. These observations call for strategies to prevent S. aureus spread to more vulnerable populations where the consequences can be severe.