Global burden of human noroviruses contamination in drinking water sources and drinking water: A systematic review and meta-analysis identifying GII.4 and GII.17 as dominant genotypes.

Human Noroviruses (HuNoVs) are the leading etiologic agents responsible for viral gastroenteritis. Drinking water (DW) serves as a significant vehicle for the transmission of HuNoVs. This study aimed to assess the occurrence of HuNoVs in drinking water sources (DWS) and DW. A systematic search spanning Web of Science, EMBASE, PubMed, and Cochrane Central Register of Controlled Trials was executed up to July 15, 2024. Following rigorous screening, 76 eligible studies underwent meta-analysis with heterogeneity assessment via Stata 14.0 using a random-effects model. The results indicated that the pooled occurrence of HuNoVs was 11 % (95 % CI: 8-14), with occurrence of 15 % (95 % CI: 10-21) in DWS and 6 % (95 % CI: 3-9) in DW. Subgroup meta-analysis demonstrated that genogroup II (GII) of HuNoVs exhibited the highest contamination occurrence of 7 % (95 % CI: 4-10), with GII.4 and GII.17 being the predominant genotypes. The two continents with the highest number of studies were Asia (n = 27) and Europe (n = 19), with HuNoVs occurrence of 14 % (95 % CI: 8-22) and 15 % (95 % CI: 7-26), respectively. Furthermore, the occurrence showed no significant differences across the four seasons: in spring, the occurrence was 11 % (95 % CI: 3-23); in summer, 15 % (95 % CI: 7-25); in autumn, 11 % (95 % CI: 2-24); and in winter, 18 % (95 % CI: 10-27). These findings provided valuable epidemiological insight into the global occurrence, seasonal variation, and genotypic distribution of HuNoVs in DWS and DW, aiding policy development and public health strategies.