{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T18:13:23Z","timestamp":1790014403075,"version":"4.0.1"},"reference-count":32,"publisher":"Public Library of Science (PLoS)","issue":"9","license":[{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100009252","name":"Science for Life Laboratory","doi-asserted-by":"publisher","award":["542 C19RA:031, LPP1:008 and REPLP1:007"],"award-info":[{"award-number":["542 C19RA:031, LPP1:008 and REPLP1:007"]}],"id":[{"id":"10.13039\/501100009252","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007190","name":"Sveriges Regering","doi-asserted-by":"publisher","award":["S2024\/00187"],"award-info":[{"award-number":["S2024\/00187"]}],"id":[{"id":"10.13039\/501100007190","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002805","name":"Carl Tryggers Stiftelse f\u00f6r Vetenskaplig Forskning","doi-asserted-by":"publisher","award":["CTS 22:2255"],"award-info":[{"award-number":["CTS 22:2255"]}],"id":[{"id":"10.13039\/501100002805","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007190","name":"Sveriges Regering","doi-asserted-by":"publisher","award":["S2025\/0066"],"award-info":[{"award-number":["S2025\/0066"]}],"id":[{"id":"10.13039\/501100007190","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Wastewater surveillance (WWS) of SARS-CoV-2 RNA levels offers a way to monitor virus circulation independently of clinical testing. With COVID-19 now endemic, clarifying the role of WWS within routine surveillance is essential. The aim was to evaluate the potential of WWS as an early warning indicator for COVID-19 in Sweden, based on its correlation with reported case data. The study includes data from July 2023 to December 2024, from 19 wastewater treatment plants (WWTPs), covering 43% of Sweden\u2019s population, and surveillance data of reported COVID-19 cases. Analyses were performed by WWTP, separately for Stockholm (4 WWTPs) and at a national level (19 WWTPs). We compared wastewater SARS-CoV-2 levels to reported COVID-19 cases using cross-correlation and prediction metrics following trend classification. Correlations and classification metrics were highest without time shifts. SARS-CoV-2 levels in wastewater were strongly correlated with reported COVID-19 cases, with median cross-correlation values of 0.80 across all WWTPs and 0.87 at Stockholm and national levels. Positive predictive values of wastewater data to reported cases ranged from 63\u201374%, and negative predictive values from 85\u201395%. Sensitivity and specificity in Stockholm reached 78% and 87%; at national level, 72% and 84%, respectively. Under the evaluated weekly sampling and reporting system, WWS did not demonstrate a consistent early-warning advantage over reported cases but may support monitoring of trends when clinical testing is reduced.<\/jats:p>","DOI":"10.1371\/journal.pone.0358326","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T17:37:19Z","timestamp":1790012239000},"page":"e0358326","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Evaluation of wastewater SARS-CoV-2 surveillance for monitoring COVID-19 trends and early warning in Sweden, 2023\u20132024"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-7389-5319","authenticated-orcid":true,"given":"Anna","family":"Ohlson","sequence":"first","affiliation":[{"name":"Public Health Agency of Sweden","place":["Solna, Sweden"],"department":["Department of Communicable Disease Control and Health Protection"]},{"name":"ECDC Fellowship Programme, Field Epidemiology path (EPIET), European Centre for Disease Prevention and Control (ECDC)","place":["Stockholm, Sweden"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Moa","family":"Rehn","sequence":"additional","affiliation":[{"name":"Public Health Agency of Sweden","place":["Solna, Sweden"],"department":["Department of Communicable Disease Control and Health Protection"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sharon","family":"K\u00fchlmann Berenzon","sequence":"additional","affiliation":[{"name":"Public Health Agency of Sweden","place":["Solna, Sweden"],"department":["Department of Public Health Analysis and Data Management"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erik","family":"Stureg\u00e5rd","sequence":"additional","affiliation":[{"name":"Public Health Agency of Sweden","place":["Solna, Sweden"],"department":["Department of Communicable Disease Control and Health Protection"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rakel","family":"Brodin","sequence":"additional","affiliation":[{"name":"Public Health Agency of Sweden","place":["Solna, Sweden"],"department":["Department of Communicable Disease Control and Health Protection"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8063-7156","authenticated-orcid":true,"given":"Anna J.","family":"Sz\u00e9kely","sequence":"additional","affiliation":[{"name":"Science for Life Laboratory, Swedish University of Agricultural Sciences","place":["Uppsala, Sweden"],"department":["Department of Aquatic Sciences and Assessment"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sofia","family":"Persson","sequence":"additional","affiliation":[{"name":"Science for Life Laboratory, Swedish University of Agricultural Sciences","place":["Uppsala, Sweden"],"department":["Department of Aquatic Sciences and Assessment"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilias","family":"Galanis","sequence":"additional","affiliation":[{"name":"Public Health Agency of Sweden","place":["Solna, Sweden"],"department":["Department of Public Health Analysis and Data Management"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,9,21]]},"reference":[{"key":"pone.0358326.ref001","doi-asserted-by":"crossref","first-page":"141364","DOI":"10.1016\/j.scitotenv.2020.141364","article-title":"Shedding of SARS-CoV-2 in feces and urine and its potential role in person-to-person transmission and the environment-based spread of COVID-19","volume":"749","author":"DL Jones","year":"2020","journal-title":"Sci Total Environ"},{"key":"pone.0358326.ref002","unstructured":"World Health Organization. Environmental surveillance for SARS-CoV-2 to complement public health surveillance - Interim Guidance. 2022."},{"issue":"6","key":"pone.0358326.ref003","doi-asserted-by":"crossref","DOI":"10.1016\/j.medj.2022.04.001","article-title":"Gastrointestinal symptoms and fecal shedding of SARS-CoV-2 RNA suggest prolonged gastrointestinal infection","volume":"3","author":"A Natarajan","year":"2022","journal-title":"Med"},{"key":"pone.0358326.ref004","doi-asserted-by":"crossref","first-page":"129848","DOI":"10.1016\/j.jhazmat.2022.129848","article-title":"Correlation between SARS-CoV-2 RNA concentration in wastewater and COVID-19 cases in community: A systematic review and meta-analysis","volume":"441","author":"X Li","year":"2023","journal-title":"J Hazard Mater"},{"issue":"9","key":"pone.0358326.ref005","doi-asserted-by":"crossref","DOI":"10.1016\/j.heliyon.2024.e30600","article-title":"A scoping review of global SARS-CoV-2 wastewater-based epidemiology in light of COVID-19 pandemic","volume":"10","author":"SA Rashid","year":"2024","journal-title":"Heliyon"},{"issue":"33","key":"pone.0358326.ref006","doi-asserted-by":"crossref","first-page":"2400096","DOI":"10.2807\/1560-7917.ES.2024.29.33.2400096","article-title":"A survey of the representativeness and usefulness of wastewater-based surveillance systems in 10 countries across Europe in 2023","volume":"29","author":"G Benedetti","year":"2024","journal-title":"Euro Surveill"},{"key":"pone.0358326.ref007","unstructured":"European Commission. Commission Recommendation (EU) 2021\/472 of 17 March 2021 on a common approach to establish a systematic surveillance of SARS-CoV-2 and its variants in wastewater in the EU. 2021."},{"issue":"46","key":"pone.0358326.ref008","doi-asserted-by":"crossref","DOI":"10.2807\/1560-7917.ES.2023.28.46.2300595","article-title":"Early detection of the emerging SARS-CoV-2 BA.2.86 lineage through integrated genomic surveillance of wastewater and COVID-19 cases in Sweden, weeks 31 to 38 2023","volume":"28","author":"C Espinosa-Gongora","year":"2023","journal-title":"Euro Surveill"},{"key":"pone.0358326.ref009","doi-asserted-by":"crossref","first-page":"121223","DOI":"10.1016\/j.watres.2024.121223","article-title":"Results from the SARS-CoV-2 wastewater-based surveillance system in Denmark, July 2021 to June 2022","volume":"252","author":"LW Krogsgaard","year":"2024","journal-title":"Water Res"},{"issue":"7","key":"pone.0358326.ref010","doi-asserted-by":"crossref","first-page":"511","DOI":"10.1021\/acs.estlett.0c00357","article-title":"Presence of SARS-Coronavirus-2 RNA in Sewage and Correlation with Reported COVID-19 Prevalence in the Early Stage of the Epidemic in The Netherlands","volume":"7","author":"G Medema","year":"2020","journal-title":"Environ Sci Technol Lett"},{"issue":"1","key":"pone.0358326.ref011","doi-asserted-by":"crossref","first-page":"4313","DOI":"10.1038\/s41467-022-31753-y","article-title":"An analysis of 45 large-scale wastewater sites in England to estimate SARS-CoV-2 community prevalence","volume":"13","author":"M Morvan","year":"2022","journal-title":"Nat Commun"},{"issue":"2","key":"pone.0358326.ref012","doi-asserted-by":"crossref","DOI":"10.1002\/jmv.28587","article-title":"Monitoring of SARS-CoV-2 concentration and circulation of variants of concern in wastewater of Leuven, Belgium","volume":"95","author":"A Rector","year":"2023","journal-title":"J Med Virol"},{"issue":"10","key":"pone.0358326.ref013","doi-asserted-by":"crossref","DOI":"10.1016\/j.heliyon.2023.e20571","article-title":"Trends in SARS-CoV-2 clinically confirmed cases and viral load in wastewater: A critical alignment for Padua city (NE Italy)","volume":"9","author":"T Baldovin","year":"2023","journal-title":"Heliyon"},{"key":"pone.0358326.ref014","unstructured":"Public Health Scotland [Internet]. Scotland; Evaluation of the Public Health Utility of Wastewater-based Surveillance for Monitoring SARS-CoV-2 in Scotland. 2024. 2024 [cited 2025 Apr 20]. Available from: https:\/\/publichealthscotland.scot\/publications\/evaluation-of-the-public-health-utility-of-wastewater-based-surveillance-for-monitoring-sars-cov-2-in-scotland\/evaluation-of-the-public-health-utility-of-wastewater-based-surveillance-for-monitoring-sars-cov-2-in-scotland"},{"issue":"1","key":"pone.0358326.ref015","doi-asserted-by":"crossref","first-page":"1714","DOI":"10.1186\/s12889-023-16627-2","article-title":"Evaluation of the pilot wastewater surveillance for SARS-CoV-2 in Norway, June 2022 - March 2023","volume":"23","author":"E Amato","year":"2023","journal-title":"BMC Public Health"},{"key":"pone.0358326.ref016","unstructured":"Public Health Agency of Sweden [Internet]. Stockholm; Covid-19 veckorapporter (weekly COVID-19 reports, Swedish). 2025 [cited 2025 Apr 20]. 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