Prevalence, antimicrobial susceptibility and genotypic characteristics of Staphylococcus aureus in Tanzania: a systematic review

Abstract

Abstract Background Data on the prevalence, genotypes and antibiotic resistance patterns of colonizing and infection-associated Staphylococcus aureus (S. aureus) strains both in humans and animals in Tanzania are scarce. Given the wide range of infections caused by S. aureus and the rise of methicillin-resistant S. aureus (MRSA) globally, this review aims at collecting published data on S. aureus bacterium to improve our understanding of its epidemiology in Tanzania. Main body We carried out a systematic review of scientific studies reporting on prevalence, antibiotic resistance and genotyping data pertaining to S. aureus in human and animal infection and colonization. The literature extracted from electronic databases such as PubMed and Google Scholar was screened for eligibility and relevant articles were included. The review is limited to manuscripts published in English language between the years 2010 and 2020. A total of 45 studies conducted in 7 of the 9 administrative zones in Tanzania were reviewed to gather data on S. aureus prevalence in humans and animals. Prevalence in humans ranged from 1 to 60%. Antibiotic resistance patterns of S. aureus isolated from colonized humans showed high resistance rates against co-trimoxazole (46%) and erythromycin (41%) as compared to reports from studies conducted outside Africa. The review suggests an increased MRSA prevalence of up to 26% as compared to 6–16% reported in previous years. Genotypic data reviewed suggested that MRSA predominantly belonged to ST88. The prevalence of S. aureus in animal studies ranged from 33 to 49%, with 4 to 35% of MRSA isolates. Most studies reported low antibiotic resistance levels, with the exception of penicillin (85%) and ampicillin (73%). Conclusion The prevalence of S. aureus and MRSA in Tanzania is rising, although clear variations between different geographic areas could be observed. Non-susceptibility to commonly prescribed antibiotics in community-associated S. aureus is of concern. Research strategies to ameliorate our knowledge on S. aureus epidemiology should employ regular antibiotic resistance surveillance, antimicrobial stewardship as well as genotypic characterization.