Viable Norovirus Fate During Water and Wastewater Treatment Operations

Norovirus is the virus that causes the commonly known 'stomach flu'. It has been difficult to study the health risk of this virus because it does not grow in the laboratory. A new method using 'human intestinal enteroids cells,' or HIEs, now allows norovirus to be grown in the laboratory. This research project will use HIEs to measure infectious norovirus in water. The study will investigate how this virus is removed by water treatments. Ultimately, this information will help ensure safe water and potentially facilitate reuse of treated wastewater. This project will also support outreach to a local Boy's and Girl's Club to give career day talks. The project will also develop water quality learning modules for high school students and engage the public in science education through public 'Science at Sunset' and 'Science Sundays' sessions. Norovirus, a critical waterborne pathogen, is predicted to account for most infections from exposure to sewage-contaminated water. Understanding the fate of norovirus in the water environment is thus crucial for addressing pressing water management challenges, including wastewater reuse and ensuring recreational and agricultural water safety. Norovirus has historically been unculturable in the laboratory. Thus, current measurements of norovirus fate in water and wastewater treatment systems rely on molecular or surrogate methods with unknown agreement with infectious norovirus. Recent culture models based on HIEs have enabled the cultivation of norovirus. The project will use HIEs to characterize infectious norovirus fate in water and wastewater using controlled laboratory experiments and samples from full-scale systems. Examples of processes that will be evaluated include chlorine and ultraviolet disinfection, membrane treatment, and an activated sludge process. This research will also enable the assessment of the agreement of culture, molecular, and surrogate measures of infectious norovirus fate in water. Cultivation of norovirus in HIEs remains highly specialized; thus, validating molecular or surrogate approaches to understand norovirus fate would enable and support additional research in this critical arena using more accessible tools. Finally, HIE-cultured samples will be paired with metagenomic sequencing to develop a 'shotgun culturing' approach to identify the infectious virome from wastewater samples. Ultimately, this work will provide the most comprehensive evaluation of norovirus fate in water and wastewater treatment systems, informing water quality monitoring and design of wastewater reuse systems. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.