Wastewater-Based Surveillance for Antimicrobial Resistance in Lowand Middle-Income Countries: A Narrative Review

Hospital-based antimicrobial resistance (AMR) surveillance misses information from asymptomatic individuals and the community at large. Wastewater-based (WBS) surveillance is a viable alternative. This review aimed to identify current WBS surveillance practices in Low- and Middle-Income Countries, outline areas of convergence and divergence, and identify gaps for future work. A literature search was carried out on Google Scholar using the queries ―wastewater-based surveillance‖ OR ―wastewater-based epidemiology‖ AND ―antimicrobial resistance‖ OR ―antibiotic resistance genes‖ AND ―low- and middle-income countries‖. We reduced the initial 957 papers to 31 articles after excluding reviews, meta-analyses, letters, conference abstracts, and commentaries. We assessed the 31 articles for methodology and findings. We found surveillance methods to be either culture-dependent or culture-independent. Culture—dependent methods required isolating and characterizing pathogens. Cultureindependent methods included quantitative polymerase chain reaction (qPCR), high-throughput qPCR, metagenomic sequencing, Oxford Nanopore-based whole-genome sequencing, and measuring pharmaceutical residues and chemical markers. The studies agreed that AMR findings in wastewater properly reflected AMR patterns in the population. Disagreements remained over the best wastewater sampling method, the impact of tourism, and the effect of seasonal changes on local antimicrobial resistance profiles. The review shows a need for more longitudinal studies, as well as studies that link clinical AMR data and antibiotic use in a given environment to corresponding environmental data. It also provides an evidence base and research agenda for scaling WBS in resource-limited settings. Wastewater-based surveillance for AMR is a viable, cost-efficient option for monitoring AMR in resource-poor settings. Therefore, it should be integrated into the national antimicrobial resistance surveillance system. The government should also prioritise investment in portable sequencing platforms and rapid analytical methods to strengthen timely detection of emerging AMR threats.

Keywords: Antimicrobial Resistance, Wastewater-Based Surveillance, Low- and Middle-Income Countries