Environmental surveillance of pathogens in Africa

Abstract

ABSTRACT The control of infectious diseases depends on effective diagnostics and interventions. In Africa, resource limitations hinder clinical surveillance. Environmental surveillance (ES), particularly wastewater surveillance, offers a cost-effective alternative. While globally expanding, its application in Africa remains limited. This review aimed to describe published studies in Africa that have utilized ES for the detection of infectious pathogens of public health importance in Africa. The study employed a rapid review approach to synthesize evidence on ES of infectious pathogens in Africa, following guidance from the Cochrane Rapid Reviews Methods. Articles from major databases, including Scopus, PubMed, Science Direct, and Cochrane, were screened using Catchii.org. Duplicates were removed, and data were extracted into Excel, and study quality was appraised using the AXIS tool and a modified Newcastle-Ottawa Scale. The search strategy identified 2,189 articles, of which 90 were found to be eligible. We identified 47 microbial species that have been reported across studies. These consisted of 46.8% bacteria ( n = 22), 36.2% viruses ( n = 17), 4.3% fungi ( n = 2), and 12.7% parasites ( n = 6). Among viruses identified, SARS-CoV-2 was the most common, followed by rotaviruses and polioviruses. Vibrio cholerae was mostly reported among bacterial pathogens. The most common sampling method was grab sampling ( n = 85, 94.4%), while two-phase separation ( n = 22, 37.3%) and filtration ( n = 11, 39.3%) were the most frequently used concentration methods for viral and bacterial detection, respectively. ES of infectious pathogens in Africa remains limited. There is a need to expand this to enhance pathogen monitoring, transmission insights, and preparedness for emerging variants.