Co-prevalence of SARS-CoV-2 and Noroviruses in Wastewater Collection and Treatment Facilities of the Eastern Cape Region, South Africa: An Exacerbated Public and Environmental Health Risk Concern.

Severe acute respiratory syndrome Coronavirus-2, Norovirus GI and GII have been identified as one of the leading primary agents of lethal diseases such as COVID-19 and acute gastroenteritis, causing critical problems in public health, particularly in children, the elderly, and individuals with weakened immune systems. These pathogens contribute to substantial morbidity, mortality and pose a serious threat to human health, imposing a tremendous economic burden globally. Hence, this study sought to profile the co-occurrence of SARS-CoV-2 and Noroviruses in wastewater collection and treatment facilities within Buffalo City and Amathole District regions, Eastern Cape Province, South Africa. Raw wastewater samples were collected from the wastewater treatment facilities on a weekly basis for a 6-month sampling regime using the grab sampling technique. Total Ribonucleic acids (RNA) were extracted and purified using the commercial Total RNA extraction kits and the extracted RNA sample were further profiled for the presence of SARS-CoV-2 RNA and Noroviruses GI and GII using RT-qPCR. A total of 213 samples were screened using RT-qPCR. SARS-CoV-2 was detected in 146 (69%) samples, Norovirus GI in 58 (27%), Norovirus GII in 25 (12%) and 25 (12%) samples showed co-infection with both GI and GII norovirus targets. The RNA concentration of the extracted samples from wastewater treatment facilities in this study ranged between 102 ng/µl and 12,828 ng/µl. It was observed that the SARS-CoV-2 GC/mL range from 5.22 × 102 to an extreme 2.5650 × 104 GC/mL. The study findings demonstrate a high prevalence of SARS-CoV-2 RNA in wastewater, affirming the utility of wastewater surveillance as an early warning system for potential outbreaks at community levels. Furthermore, the study showed the co-occurrence of SARS-CoV-2 alongside Norovirus GI and GII in wastewater milieu, highlighting an exacerbated potential risk of co-infection and a major threat to public health and environmental safety.