Systematic review and meta-analysis of Staphylococcus aureus at the human-animal-environment Interface in eastern Africa: Prevalence, virulence genes, and antimicrobial resistance profile.

BACKGROUND

Staphylococcus aureus (S. aureus) is a major pathogen affecting humans, animals, and the environment (HAE) and poses a critical global health threat due to its ability to develop antimicrobial resistance (AMR), including methicillin-resistant S. aureus (MRSA). Although numerous studies have reported on S. aureus in East Africa, the findings are scattered and vary in methodology, making it difficult to understand regional prevalence, AMR patterns, and virulence profiles. This systematic review and meta-analysis synthesizes existing evidence to provide a comprehensive overview, informing regional public health strategies, antimicrobial stewardship, and targeted interventions to control the spread of resistant S. aureus.

METHODS

Following PRISMA guidelines, a comprehensive search of major electronic databases (PubMed, African Journals Online, SCOPUS, M-libraries, Web of Science, and HINARI) was conducted for English-language cross-sectional studies published between 2000 and 2024 reporting S. aureus detection at the HAE interface or on occupational equipment in East Africa. Studies meeting predefined inclusion criteria underwent quality assessment using the Joanna Briggs Institute checklist. Pooled prevalence rates were calculated using a random-effects model meta-analysis, with heterogeneity assessed via I2 statistics and Cochran's Q test. Publication bias was evaluated using funnel plots and Egger's regression tests.

RESULTS

From 4748 initial articles, 28 studies were included, revealing an overall S. aureus prevalence of 19 % (95 % CI: 14-25 %) across the HAE interface, exhibiting significant heterogeneity (I2 = 98 %). Subgroup analysis indicated the highest prevalence in Tanzania (26 %), followed by Ethiopia (19 %) and Kenya (18 %). AMR analysis demonstrated substantial resistance to penicillin (88.82 %), ampicillin (58.96 %), and tetracycline (45.73 %), with multidrug resistance (MDR) detected in 39.55 % of isolates and MRSA prevalence at 27.63 %. Key resistance genes, including mecA, blaZ, tet(K), and erm(C), were identified, alongside virulence genes like pvl and tsst-1.

CONCLUSION

This review emphasizes the imperative need for interventions, including the enhancement of antimicrobial stewardship, the advancement of surveillance systems, and the implementation of One Health strategies to curtail the issues of AMR in S. aureus in East Africa.