Occurrence of Hepatitis A Virus in Water Matrices: A Systematic Review and Meta-Analysis.

Hepatitis A is a common form of viral hepatitis. It is usually transmitted through the ingestion of contaminated food and water. This systematic review was carried out to summarise the overall prevalence of Hepatitis A virus (HAV) in different water matrices: untreated and treated wastewater, surface water, groundwater, drinking water, and others (e.g., irrigation water and floodwater). The literature search was performed in four databases: PubMed, Web of Science, Global Index Medicus, and Excerpta Medica Database. Heterogeneity (I 2 ) was assessed using the χ 2 test on the Cochran Q statistic and H parameters. A total of 200 prevalence data from 144 articles were included in this meta-analysis. The overall prevalence of HAV in water matrices was 16.7% (95% CI: 13.4-20.3). The prevalence for individual matrix was as follows: 31.4% (95% CI: 23.0-40.4) untreated wastewater, 18.0% (95% CI: 9.5-28.2) treated wastewater, 15.0% (95% CI: 10.1-20.5) surface water, 2.3% (95% CI: 0.1-6.0) in groundwater, 0.3% (95% CI: 0.0-1.7) in drinking water, and 8.5% (95% CI: 3.1-15.6) in other matrices. The prevalence was higher in low-income economies (29.0%). Africa and Eastern Mediterranean were the regions with higher HAV prevalence values. This study showed a high heterogeneity (I 2 > 75%) with a significant publication bias ( p value Egger test < 0.001). The results of this review suggest that water matrices could be an important route of HAV transmission even in industrialized countries, despite the lower prevalence compared to less industrialized countries, and the availability of advanced water management systems. More effective water/wastewater treatment strategies are needed in developing countries to limit the environmental circulation of HAV.