Prevalence of common enteric viruses in municipal wastewater treatment plants and their health risks arising from wastewater reuse

Abstract

Enteric viruses are known to be prevalent in municipal wastewater, but information on the health risks arising from wastewater reuse is limited. This study quantified six common enteric viruses in raw wastewater and determined the effectiveness of different secondary and tertiary treatment processes at reducing their abundances in three full-scale wastewater treatment plants in China. In the raw wastewater, polyomavirus BK and norovirus GII (Nov GII) exhibited the highest abundance among the detected DNA and RNA viruses, respectively, with concentrations >5 log10 copies/L. Viruses in the raw wastewater were mainly removed by the secondary treatment processes, with log reduction values ranging from 1 to 2. The tertiary treatment processes of both chlorination and ultraviolet irradiation facilitated the additional reduction of viruses. The quantitative microbial risk assessment was applied to estimate the health risks of adenovirus (Adv) and Nov GII when reusing the treated wastewater for irrigation of public green spaces and crops. Estimated disability-adjusted life years of Adv and Nov GII for both reuses were higher than the risk threshold (10−6) required by the WHO in the actual scenarios. More effective treatment technologies should be implemented to remove viruses for safe reuse of the treated wastewater.

Aligning monitoring of virus barriers in potable reuse with unit process treatment mechanisms and time scales: A critical review and research needs

“…Noroviruses possess many features that make them a highly efficient human pathogen (Hall, 2012), and they are the most common cause of acute nonbacterial gastroenteritis internationally (Schwab, 2007). Adenoviruses and noroviruses have also been shown to be potentially infective at levels typical of treated wastewater (P. Liu, Li, et al, 2021). Beyond these enteric viruses, various other viruses are often present in wastewater: for example, mpox, human bocavirus, and coronaviruses have been the subject of recent studies (Booranathawornsom et al, 2022; Corpuz et al, 2020; Nelson, 2022).…”