Abstract
Wastewater-based epidemiology (WBE), an emerging approach for community-wide COVID-19 surveillance, was primarily characterized at large sewersheds such as wastewater treatment plants serving a large population. Although informed public health measures can be better implemented for a small population, WBE for neighborhood-scale sewersheds is less studied and not fully understood. This study applied WBE to seven neighborhood-scale sewersheds (average population of 1471) from January to November 2021. Community testing data showed an average of 0.004 % incidence rate in these sewersheds (97 % of monitoring periods reported two or fewer daily infections). In 92 % of sewage samples, SARS-CoV-2 N gene fragments were below the limit of quantification. We statistically determined 10 -2.6 as the threshold of the SARS-CoV-2 N gene concentration normalized to pepper mild mottle virus (N/PMMOV) to alert high COVID-19 incidence rate in the studied sewershed. This threshold of N/PMMOV identified neighborhood-scale outbreaks (COVID-19 incidence rate higher than 0.2 %) with 82 % sensitivity and 51 % specificity. Importantly, neighborhood-scale WBE can discern local outbreaks that would not otherwise be identified by city-scale WBE. Our findings suggest that neighborhood-scale WBE is an effective community-wide disease surveillance tool when COVID-19 incidence is maintained at a low level.
Keywords: Low COVID-19 incidence; Neighborhood-scale sewersheds; SARS-CoV-2 variant-specific RT-qPCR assays; Wastewater-based epidemiology.
【저자키워드】 Wastewater-based epidemiology., Low COVID-19 incidence, Neighborhood-scale sewersheds, SARS-CoV-2 variant-specific RT-qPCR assays, 【초록키워드】 COVID-19, Treatment, SARS-CoV-2, Epidemiology, virus, sensitivity, specificity, RT-qPCR, infections, Surveillance, outbreak, incidence rate, Mild, Disease surveillance, N gene, plant, threshold, quantification, Concentration, public health measure, COVID-19 incidence, average, SARS-CoV-2 N gene, approach, effective, limit, Seven, reported, applied, characterized, less, statistically, local outbreak, normalized, the SARS-CoV-2, 【제목키워드】 Epidemiology, application, COVID-19 incidence,