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

Area of Science:

• Environmental microbiology
• Public health
• Epidemiology

Background:

• Human noroviruses (HuNoVs) are the primary cause of viral gastroenteritis worldwide.
• Drinking water (DW) and drinking water sources (DWS) are significant transmission routes for HuNoVs.
• Understanding the prevalence of HuNoVs in water is crucial for public health interventions.

Purpose of the Study:

• To systematically assess the global occurrence of HuNoVs in DWS and DW.
• To identify predominant HuNoVs genogroups and genotypes in water.
• To analyze seasonal variations in HuNoVs contamination.

Main Methods:

• A comprehensive meta-analysis of 76 eligible studies was conducted.
• Systematic literature searches were performed across major scientific databases up to July 15, 2024.
• Random-effects models were used to assess heterogeneity and pooled occurrence rates.

Main Results:

• The pooled occurrence of HuNoVs in DWS and DW was 11% (95% CI: 8-14%).
• Occurrence was higher in DWS (15%) compared to DW (6%).
• Genogroup II (GII), particularly GII.4 and GII.17, was the most prevalent genotype.

Conclusions:

• HuNoVs are frequently detected in global drinking water supplies, posing a continuous public health risk.
• Genogroup II strains are the dominant cause of contamination in water.
• Findings support the need for enhanced water quality monitoring and management strategies to mitigate HuNoV transmission.