Evaluation of human adenovirus and human polyomavirus as indicators of human sewage contamination in the aquatic environment

Discharge of inadequately treated human wastewater into surface waters used for recreation, drinking water, irrigation and shellfish cultivation may present a public health hazard due to the potential shedding of high concentrations of pathogenic viruses from the human gastrointestinal tract. Human adenovirus (HAdV) and human polyomavirus (HPyV) are ubiquitous in humans and have excellent survival characteristics in the environment, so are potential candidates for indicators of human sewage contamination. Using qPCR assays, the prevalence and quantity of HAdV and HPyV JC and BK were determined in influent and effluent wastewater and receiving waters (river, urban stream, estuarine), then compared with norovirus (NoV) presence, a significant human pathogen which is not necessarily ubiquitously excreted into the environment. HAdV and HPyV were frequently detected in high concentrations in wastewater and wastewater-contaminated waters confirming their use as potential indicators for the presence of human sewage. Overall, there was a correlation between the presence of HAdV and HPyV with NoV but there were some notable exceptions including the higher frequency of NoV compared to HAdV and HPyV in estuarine waters impacted by wastewater overflows. We found that HAdV and HPyV detection by qPCR was a suitable tool for evaluating water quality and that their detection can aid in determining pollution sources, thus providing useful information for health risk assessments.