Elana M. G. Chan, A. Bidwell, Zongxi Li, S. Tilmans, A. Boehm
{"title":"Public health policy impact evaluation: A potential use case for longitudinal monitoring of viruses in wastewater at small geographic scales","authors":"Elana M. G. Chan, A. Bidwell, Zongxi Li, S. Tilmans, A. Boehm","doi":"10.1371/journal.pwat.0000242","DOIUrl":null,"url":null,"abstract":"Public health policy impact evaluation is challenging to study because randomized controlled experiments are infeasible to conduct, and policy changes often coincide with non-policy events. Quasi-experiments do not use randomization and can provide useful knowledge for causal inference. Here we demonstrate how longitudinal wastewater monitoring of viruses at a small geographic scale may be used in a quasi-experimental design to evaluate the impact of COVID-19 public health policies on the spread of COVID-19 among a university population. We first evaluated the correlation between incident, reported COVID-19 cases and wastewater SARS-CoV-2 RNA concentrations and observed changes to the correlation over time, likely due to changes in testing requirements and testing options. Using a difference-in-differences approach, we then evaluated the association between university COVID-19 public health policy changes and levels of SARS-CoV-2 RNA concentrations in wastewater. We did not observe changes in SARS-CoV-2 RNA concentrations associated with most policy changes. Policy changes associated with a significant change in campus wastewater SARS-CoV-2 RNA concentrations included changes to face covering recommendations, indoor gathering bans, and routine surveillance testing requirements and availability.","PeriodicalId":93672,"journal":{"name":"PLOS water","volume":"55 25","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"PLOS water","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1371/journal.pwat.0000242","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Public health policy impact evaluation is challenging to study because randomized controlled experiments are infeasible to conduct, and policy changes often coincide with non-policy events. Quasi-experiments do not use randomization and can provide useful knowledge for causal inference. Here we demonstrate how longitudinal wastewater monitoring of viruses at a small geographic scale may be used in a quasi-experimental design to evaluate the impact of COVID-19 public health policies on the spread of COVID-19 among a university population. We first evaluated the correlation between incident, reported COVID-19 cases and wastewater SARS-CoV-2 RNA concentrations and observed changes to the correlation over time, likely due to changes in testing requirements and testing options. Using a difference-in-differences approach, we then evaluated the association between university COVID-19 public health policy changes and levels of SARS-CoV-2 RNA concentrations in wastewater. We did not observe changes in SARS-CoV-2 RNA concentrations associated with most policy changes. Policy changes associated with a significant change in campus wastewater SARS-CoV-2 RNA concentrations included changes to face covering recommendations, indoor gathering bans, and routine surveillance testing requirements and availability.