Dispersion of SARS‐CoV‐2 RNA across a wastewater treatment plant and its workers

Abstract

Within urban and suburban sewersheds, SARS‐CoV‐2 released through faeces is transported through sewage systems into municipal wastewater treatment plants (WWTPs). Studies have shown that viral RNA is detectable in untreated wastewater but not in WWTP effluent. In this study, we investigated treatment steps between the influent and final treated effluent to identify the point at which viral RNA is below detection. Additionally, we examined air surrounding high turbulence treatment steps to test for the presence of SARS‐CoV‐2 RNA in WWTP‐generated bioaerosols. To examine potential worker exposure to SARS‐CoV‐2, WWTP workers were tested for the presence of viral RNA. The data show that despite high viral RNA concentration in the influent, SARS‐CoV‐2 RNA concentration decreased significantly ( p < 0.02) in the main treatment steps and was below detection in the effluent. Additionally, SARS‐CoV‐2 RNA was below detection in air samples ( n = 42), and the worker rate of infection was not significantly different ( p = 0.99) from the rate of infection in the surrounding community. These results suggest that WWTP workers may have minimal exposure to SARS‐CoV‐2 during routine outdoor work procedures and that the WWTP successfully reduces the amount of viral RNA entering effluent receiving waters, providing a vital public health service to communities.

Fecal-oral transmission of SARS-CoV-2: A systematic review of evidence from epidemiological and experimental studies

“…After duplicates removal we screened 4869 records, from which we reviewed 152 full text documents and finally included 30 reports of 24 studies. 10 , 14 , 15 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 A list of studies excluded during full text screening is available in the Supplementary Appendix 3 along with reasons for exclusion. One possible eligible record in Chinese was identified but excluded because of non-English language.…”

SARS-CoV-2 concentration in wastewater consistently predicts trends in COVID-19 case counts by at least two days across multiple WWTP scales

“…Details of the reverse transcription droplet digital PCR assays were performed as described previously ( Isanovic et al, 2022 ) and are also available in the Supplementary Methods. A full list of assays and associated primers and probes is available in Supplementary Table S5, and reagent concentrations are given in Supplementary Table S6.…”

“…Limit of blank (LOB) and limit of detection (LOD) were calculated for the ddPCR as described previously ( Isanovic et al, 2022 ). Details are also available in the Supplementary Methods.…”

“…The number of SARS-CoV-2 genome copies per liter (GC/L) of wastewater was determined through dimensional analysis as described previously ( Isanovic et al, 2022 ). Details are also available in the Supplementary Methods.…”

Building-level wastewater surveillance of SARS-CoV-2 is associated with transmission and variant trends in a university setting

“…For ddPCR, droplets were generated using a Bio-Rad QX200 Automated Droplet Generator. Droplets were thermal cycled using a Bio-Rad C1000 Touch thermal cycler and quantified using a Bio-Rad QX200 as described previously ( Isanovic et al, 2022 ). Detailed ddPCR procedures and SARS-CoV-2 quantification are described in the supplemental methods.…”