{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T23:42:54Z","timestamp":1767915774918,"version":"3.49.0"},"reference-count":27,"publisher":"Public Library of Science (PLoS)","issue":"1","license":[{"start":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T00:00:00Z","timestamp":1767830400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/publicdomain\/zero\/1.0\/"}],"funder":[{"DOI":"10.13039\/100009054","name":"U.S. President\u2019s Emergency Plan for AIDS Relief","doi-asserted-by":"publisher","award":["NU2GGH002038"],"award-info":[{"award-number":["NU2GGH002038"]}],"id":[{"id":"10.13039\/100009054","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosglobalpublichealth.org"],"crossmark-restriction":false},"short-container-title":["PLOS Glob Public Health"],"abstract":"<jats:p>The routine COVID-19 surveillance in Malawi that relied on retrospective reporting could not efficiently steer timely measures to the rapidly evolving pandemic. To monitor real-time changes in infections and inform the COVID-19 response, we implemented an active sentinel surveillance system from July to December 2022. Symptomatic and asymptomatic patients with SARS-CoV-2 in selected health facilities (HFs) and anyone aged \u22655 years entering at Point of Entry (PoEs) sites were eligible to participate. Self-reported epidemiological and clinical data, and nasopharyngeal specimens were collected from 9,305 participants. A higher overall SARS-CoV-2 RT-PCR positivity rate was observed at HFs, 8.9% among symptomatic and 6.5% among asymptomatic patients, versus 3.5% at PoEs. The positivity trends among symptomatic and asymptomatic patient groups showed a similar pattern throughout the period. This active surveillance complemented routine surveillance, especially during a low incidence period and highlighted the need to target both symptomatic and asymptomatic populations.<\/jats:p>","DOI":"10.1371\/journal.pgph.0004158","type":"journal-article","created":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T18:27:49Z","timestamp":1767896869000},"page":"e0004158","update-policy":"https:\/\/doi.org\/10.1371\/journal.pgph.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Monitoring COVID-19 occurrence in a resource-limited setting \u2013 COVID-19 sentinel surveillance in 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