ABSTRACT

Hospitals may be a significant reservoir of antibiotic-resistant genes, including carbapenemase genes. This study aimed to evaluate the prevalence and distribution of carbapenemase genes in hospital wastewater in Africa.

We conducted a comprehensive search on carbapenemase genes in hospital wastewater in Africa up to November 31, 2024, using PubMed, Google Scholar, and African Journal Online (AJOL) databases. We included original studies without time or language restrictions. The meta-analysis used the R package ‘metafor’ with a random effects model due to expected heterogeneity among studies. Heterogeneity was assessed using the I2 statistic.

We included 13 studies conducted in seven African countries. Compared with those in treated wastewater, carbapenem genes were more enriched in raw wastewater. Among the 13 different carbapenemase genes reported, 9 (69.2%) genes were specific to the raw wastewater group, including blaIMP, blaVIM, blaOXA-181, blaOXA-69, blaOXA-1-like, blaOXA-48-like, blaGES, blaOXA-416, and blaOXA-51. They are more commonly isolated from enterobacteria (7; 58.3%). The estimated overall prevalence was 23.8% (95% CI: 15.4% 1–33.4%), and the heterogeneity between studies was substantial (I2 = 96.1%; p<0.01).

This review emphasizes the presence of carbapenemase genes in hospital wastewater in Africa, showing a high prevalence. African hospitals should focus on controlling the spread of these genes in wastewater and prioritize the safety of health professionals and patients.

IMPORTANCE Antibiotic resistance poses a significant threat to global public health. It is a complex process influenced by host, environmental, and pathogen factors. Effluents, especially from hospitals, are substantial sources of antibiotic-resistant bacteria due to high bacterial loads, nutrients, and low levels of antibiotics. Improper handling and disposal of hospital effluents can pose a risk to public health by promoting the spread of resistance genes. Sanitation and hospital waste management standards in Africa vary significantly. Hospital wastewater can be a significant source of antibiotic-resistance genes, including carbapenemase genes. Carbapenemases can hydrolyze penicillins, cephalosporins, and carbapenems, making them a serious public health concern as carbapenems are often the last resort antibiotics for treating multiresistant bacteria. This review aims to assess the prevalence and distribution of carbapenemase genes in hospital wastewater across Africa.

Competing Interest Statement

The authors have declared no competing interest.

Funding Statement

This study did not receive any funding.

Author Declarations

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

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I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

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Data Availability

All data produced in the present work are contained in the manuscript.

AbbreviationsAJOLAfrican Journal OnlineARBAntibiotic-resistant bacteriaGESGuiana extended-spectrum beta-lactamaseIMPImipenemaseKPCKlebsiella pneumoniae carbapenemaseMMATMixed Methods Appraisal ToolNDMNew Delhi metallo beta-lactamaseOXAOxacillinasesPRISMAPreferred Reporting Items for Systematic Reviews and Meta-AnalysesPROSPEROInternational prospective register of systematic reviewsVIMVerona Integron encoding metallo beta-lactamase.