Prevalence of Staphylococcus aureus Nasal Carriage and Methicillin-resistant S. aureus Among Medical Students: A Systematic Review and Meta-analysis

Context: Evaluating the prevalence of Staphylococcus aureus nasal carriage and methicillin-resistant S. aureus (MRSA) that are sources of nosocomial infection among medical students. Evidence Acquisition: Electronic databases were searched by preferred subject headings and free-text keywords. After omitting duplicates, retrieved articles were screened by two independent reviewers in a three-step process based on inclusion criteria. Then, reviewers critically appraised the selected studies by JBI checklists and extracted the required data. Finally, the pooled prevalence rates of S. aureus nasal carriage and MRSA were meta-analyzed by Stata V.16 software. The heterogeneity of included studies was calculated by I2 and chi-square. Subgroup analysis was carried out according to study designs, as well as the continent origin of clinical and preclinical students. Results: Of 858 retrieved studies, 15 were included in the meta-analysis. The results showed that the pooled prevalence of nasal S. aureus carriage was 28% [prevalence rate: 0.028, 95% CI: 0.21 - 0.34, P < 0.001, I2: 96.40%, chi2: 360.98 (df = 14)]. The prevalence of S. aureus among clinical students was 33% (pooled prevalence rate: 0.33, 95% CI: 0.18 - 0.47) whereas, in preclinical students, it was 25% (pooled prevalence rate: 0.25, 95% CI: 0.23 - 0.28). Also, in a subgroup analysis of continents, Australia (Oceania) had the highest prevalence rate. According to an evaluation of publication bias, the distribution of studies was very high. Moreover, pooled MRSA prevalence among medical students was 2% (prevalence rate: 0.02 95% CI: 0.01 - 0.03, P < 0.001). Conclusions: In this meta-analysis, S. aureus and MRSA prevalence rates among medical students were estimated at 28% and 2%, respectively. More attention should be given to the prevention of MRSA colonization and screening strategies among medical students across the world.