The prevalence of antimicrobial drug resistance of non-typhoidal Salmonella in human infections in sub-Saharan Africa: a systematic review and meta-analysis

Introduction: Non-typhoidal Salmonella (NTS) bacteremia is common in sub-Saharan Africa. We examined the prevalence of antibiotic resistance to fluoroquinolones, third-generation cephalosporins, and multi-drug resistance (MDR) in NTS human isolates from sub-Saharan Africa. Methods: A systematic review was conducted using a search in Ovid Medline, Embase, and African Index Medicus of publications between 2000 and 2021. A random-effects model meta-analysis was performed using data from 66 studies that included 29,039 NTS blood and 1,065 stool isolates. Results: The pooled prevalence proportions of MDR were 0.685 (95% CI 0.574–0.778) and 0.214 (0.020–0.785) in blood vs. stool isolates. The corresponding estimates of fluoroquinolones resistance were 0.014 (0.008–0.025) vs. 0.021 (0.012–0.036) and third-generation cephalosporins resistance 0.019 (0.012–0.031) vs. 0.035 (0.006–0.185). Similar results were found for children and adults. Resistance prevalence to these antibiotics in blood isolates increased between 2000–2010 and 2011–2021. The guidelines employed to determine antimicrobial resistance and epidemiological characteristics (e.g. sample size, study duration) correlated with the resistance prevalence. Conclusions: The prevalence of MDR and resistance to fluoroquinolones and third-generation cephalosporins in NTS in sub-Saharan Africa is alarming. Expert opinion: Standardized surveillance of antimicrobial drug resistance in NTS in sub-Saharan Africa is warranted to guide healthcare policymaking and antibiotic stewardship programs.