A one-step centrifugal ultrafiltration method to concentrate enteric viruses from wastewater

A one-step centrifugal ultrafiltration method was developed to enhance rapid detection of human enteric viruses and co-occurring viruses in wastewater. Samples were collected pre- and post-UV treatment at two full-scale tertiary municipal wastewater treatment plants in Calgary, Canada. Viruses were concentrated from 100mL wastewater samples through direct centrifugation using the Centricon Plus-70 ultrafilter. Seven viruses, including norovirus, rotavirus, sapovirus, astrovirus, enterovirus, adenovirus and JC virus, were tested using real-time quantitative PCR (rt-qPCR) and cell culture. All of the viruses were detected in pre- and post-UV samples by rt-qPCR, with rotavirus the most numerous (6.6 log₁₀ GE copies/L). Infectious viruses, by cell culture, were found in all tested pre-UV samples but only in one post-UV sample. The results were comparable and consistent to that obtained using virus adsorption-elution method, indicating that the centrifugal ultrafiltration method is adequate to retain the viruses and maintain their infectivity during processing. As a simple, rapid and cost-effective method to screen wastewater viruses, this one-step centrifugal ultrafiltration method may serve as an effective approach to assess virus removal and gain knowledge of human virus activity during wastewater treatment.