Estimating wastewater concentrations of norovirus and rotavirus from global data on community-level infection prevalence and viral shedding

ABSTRACT Water quality modelling offers the opportunity of estimating the magnitude of pathogen loads into wastewater by using data on disease prevalence and excretion. The objective of this paper is to reflect on the potential of using prevalence and excretion rate data from the literature to simulate wastewater concentrations for norovirus and rotavirus. Three systematic literature reviews were carried out to collect worldwide data. Firstly, targeting community-level prevalence data, secondly, viral excretion rates in faecal material, and thirdly, concentrations in wastewater. Data collected in the first two reviews were input to simulate concentrations in wastewater. Model results were compared with reported concentrations collected in the latest review. Of 2,193 studies, 97 were included. Reported community-level prevalence of infection ranged from 0.22 to 9.5% for norovirus and 0 to 3.3% for rotavirus. Mean viral excretion was 4.9 × 1010 and 9.7 × 108 GC/g stool for norovirus and rotavirus, respectively. Average reported wastewater concentrations were 1.5 × 107 and 2.4 × 107 GC/100 mL, respectively. Modelled concentrations were generally higher than observed values. This synthesis demonstrates the potential of integrating prevalence and excretion data through modelling to estimate pathogen loads in wastewater while highlighting major sources of variability and the need for more data collection on prevalence and excretion.