Evaluation of Sampling, Analysis, and Normalization Methods for SARS-CoV‑2 Concentrations in Wastewater to Assess COVID-19 Burdens in Wisconsin Communities
datasetposted on 09.07.2021, 19:37 authored by Shuchen Feng, Adelaide Roguet, Jill S. McClary-Gutierrez, Ryan J. Newton, Nathan Kloczko, Jonathan G. Meiman, Sandra L. McLellan
Wastewater surveillance for SARS-CoV-2 provides an approach for assessing the infection burden across a sewer service area. For these data to be useful for public health, measurement variability and the relationship to case data need to be established. We determined SARS-CoV-2 RNA concentrations in the influent of 12 wastewater treatment plants from August 2020 to January 2021. Technical replicates for N1 gene concentrations showed a relative standard deviation of 24%, suggesting it is possible to track relatively small (∼30%) changes in SARS-CoV-2 concentrations over time. COVID-19 cases were correlated significantly (ρ ≥ 0.70) to wastewater SARS-CoV-2 RNA concentrations across large and small service areas, with weaker relationships (ρ ≥ 0.59) in two communities. SARS-CoV-2 concentrations normalized to per capita slightly improved correlations to COVID-19 incidence, but normalizing to a spiked recovery control (BCoV) or a fecal marker (PMMoV or HF183) reduced correlations for a number of plants. Daily sampling demonstrated that a minimum of two samples collected per week were needed to maintain accuracy in trend analysis. The differences in the strength of SARS-CoV-2 relationships to COVID-19 incidence and the effect of normalization on these data among communities demonstrate that rigorous validation should be performed at individual sites where wastewater surveillance programs are implemented.
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service areasDaily samplingsewer service areaAugust 2020COVID -19 casesWisconsin Communities Wastewater su...HFN 1 gene concentrationsSARS-CoV -2 concentrationsCOVID -19 incidencemeasurement variabilitywastewater SARS-CoV -2 RNA concentr...COVID -19 Burdenscase data needinfection burdenSARS-CoV -2SARS-CoV -2 RNA concentrationsNormalization Methodsrecovery control12 wastewater treatment plantstrend analysisJanuary 2021. Technical replicateswastewater surveillance programsSARS-CoV -2 relationships