Environmental surveillance of human enteric viruses in wastewaters, groundwater, surface water and sediments of Campania Region

Abstract

Enteric viruses represent a public health risk since they are involved in foodborne and waterborne outbreaks. The aim of this study was to investigate the circulation of select human enteric viruses — hepatitis A virus (HAV), noroviruses (NoVGI and NoVGII), adenovirus (AdV), rotavirus (RV), astrovirus (AsV), sapovirus (SaV) and aichivirus (AiV) – in wastewater and in environmental samples (groundwater, surface water and sediments) of Campania Region, southern Italy, with the goal of evaluating their circulation in the environment and to characterize the circulating strains by phylogenetic analysis. A total of 199 water and sediment samples were collected from rivers, dams, wells and wastewater treatment plants (WWTPs) in all provinces of the Campania Region and analysed by real-time qPCR for the detection of viruses, after a concentration step with organic flocculation. This study provides information on the qualitative and quantitative spread of human enteric viruses in the environment and their potential health risk. In our samples all the viral families were detected, with different prevalence. Among the investigated viruses, RV was the most prevalent and concentrated virus in surface water and sediments, with AsV being prevalent and concentrated in wastewater. The prevalence of viral pathogens was not influenced by season for almost all enteric viruses, except for NoVGII in WWTPs. Within the WWTPs, a significant reduction in the average concentration levels was observed for all viral targets from the influent to the effluent except for the HAV and AiV. The results of our study confirmed the importance of environmental surveillance that can represent a key tool for pollution control and human risk exposure.