{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T17:54:38Z","timestamp":1791482078989,"version":"4.3.4"},"reference-count":33,"publisher":"Public Library of Science (PLoS)","issue":"10","license":[{"start":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T00:00:00Z","timestamp":1791417600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosdigitalhealth.org"],"crossmark-restriction":false},"short-container-title":["PLOS Digit Health"],"abstract":"<jats:p>\n                    FluSurvey is a participatory surveillance system used to monitor trends in influenza and other respiratory viruses through weekly symptom surveys among the UK population. We aimed to characterise the wider impact of \u201cinfluenza-like illnesses\u201d (ILI) among FluSurvey participants and assess correlations of ILI with other established influenza surveillance systems. We included data reported by FluSurvey participants over the 2023\u201324 and 2024\u201325 winter seasons. Using weekly symptoms surveys, we derived ILI episodes and estimated the proportion reporting healthcare service use, medication use, impact on daily life, absenteeism and use of tests. We applied existing methodologies (omitting first report and weighting to the age-sex structure of England) and assessed cross-correlations of weekly FluSurvey ILI rates with the national surveillance of GP ILI consultations, influenza hospital admissions, and influenza PCR test positivity at time lags of up to +\/-2 weeks. There were 3057 participants over two winter seasons (N\n                    <jats:sub>2023-24<\/jats:sub>\n                    \u2009=\u20092540, 63% female, mean age 60 years; N\n                    <jats:sub>2024-25<\/jats:sub>\n                    \u2009=\u20092273, 64% female, mean age 61 years). Of 1868 ILI episodes, only a minority contacted healthcare services (14%, most frequently visiting the GP). A large proportion of episodes reported medication use (89%), impact on daily life (75%) and missing school or work (47%). Testing frequency notably declined in the 2024\u201325 season compared to 2023\u201324. FluSurvey ILI rates were strongly correlated with other influenza surveillance, predominantly leading GP ILI consultations (max r\u2009=\u20090.73), coinciding with influenza hospital admissions (max r\u2009=\u20090.88) and lagging influenza test positivity (max r\u2009=\u20090.88). The majority of ILI reported to FluSurvey do not contact healthcare due to symptoms but experienced wider impacts on daily life. FluSurvey ILI corresponds well with other national influenza surveillance and provides broader context on community illness, supplementing the monitoring of influenza activity for public health response.\n                  <\/jats:p>","DOI":"10.1371\/journal.pdig.0001714","type":"journal-article","created":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T17:21:42Z","timestamp":1791480102000},"page":"e0001714","update-policy":"https:\/\/doi.org\/10.1371\/journal.pdig.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Monitoring influenza-like symptoms in the UK through participatory surveillance: Insights from FluSurvey over two winter seasons (2023-24 and 2024-25)"],"prefix":"10.1371","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0513-5188","authenticated-orcid":true,"given":"Rebecca E.","family":"Green","sequence":"first","affiliation":[{"name":"UK Health Security Agency","place":["London, United Kingdom"],"department":["Immunisation and Vaccine Preventable Diseases Division"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathon","family":"Mellor","sequence":"additional","affiliation":[{"name":"UK Health Security Agency","place":["London, United Kingdom"],"department":["Chief Data Officer Group"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher","family":"Rawlinson","sequence":"additional","affiliation":[{"name":"UK Health Security Agency","place":["London, United Kingdom"],"department":["Immunisation and Vaccine Preventable Diseases Division"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elizabeth","family":"Waller","sequence":"additional","affiliation":[{"name":"UK Health Security Agency","place":["London, United Kingdom"],"department":["Immunisation and Vaccine Preventable Diseases Division"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nurin","family":"Abdul Aziz","sequence":"additional","affiliation":[{"name":"UK Health Security Agency","place":["London, United Kingdom"],"department":["Immunisation and Vaccine Preventable Diseases Division"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Conall H.","family":"Watson","sequence":"additional","affiliation":[{"name":"UK Health Security Agency","place":["London, United Kingdom"],"department":["Immunisation and Vaccine Preventable Diseases Division"]},{"name":"Imperial College London","place":["London, United Kingdom"],"department":["NIHR Health Protection Research Unit in Respiratory Infections"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gavin","family":"Dabrera","sequence":"additional","affiliation":[{"name":"UK Health Security Agency","place":["London, United Kingdom"],"department":["Immunisation and Vaccine Preventable Diseases Division"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,10,8]]},"reference":[{"issue":"1","key":"pdig.0001714.ref001","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1016\/S2213-2600(18)30496-X","article-title":"Mortality, morbidity, and hospitalisations due to influenza lower respiratory tract infections, 2017: an analysis for the Global Burden of Disease Study 2017","volume":"7","author":"GBD 2017 Influenza Collaborators","year":"2019","journal-title":"Lancet Respir Med"},{"key":"pdig.0001714.ref002","article-title":"The disease burden of influenza beyond respiratory illness","author":"AE Macias","year":"2021","journal-title":"Vaccine"},{"key":"pdig.0001714.ref003"},{"key":"pdig.0001714.ref004","doi-asserted-by":"crossref","first-page":"04130","DOI":"10.7189\/jogh.13.04130","article-title":"What are the characteristics of participatory surveillance systems for influenza-like-illness?","volume":"13","author":"N Atkins","year":"2023","journal-title":"J Glob Health"},{"key":"pdig.0001714.ref005"},{"key":"pdig.0001714.ref006","doi-asserted-by":"crossref","first-page":"101820","DOI":"10.1016\/j.mex.2022.101820","article-title":"Calculating incidence of Influenza-like and COVID-like symptoms from Flutracking participatory survey data","volume":"9","author":"EP Harvey","year":"2022","journal-title":"MethodsX"},{"key":"pdig.0001714.ref007"},{"key":"pdig.0001714.ref008","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1016\/j.epidem.2015.05.001","article-title":"Ten-year performance of Influenzanet: ILI time series, risks, vaccine effects, and care-seeking behaviour","volume":"13","author":"SP van Noort","year":"2015","journal-title":"Epidemics"},{"key":"pdig.0001714.ref009","doi-asserted-by":"crossref","first-page":"232","DOI":"10.1186\/1471-2334-14-232","article-title":"Incidence and risk factors for influenza-like-illness in the UK: online surveillance using 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on rate of influenza\u2010like illness symptoms in England and Wales","author":"L Tunnicliffe","year":"2022","journal-title":"Influenza Other Respir Viruses"},{"issue":"4","key":"pdig.0001714.ref013","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pcbi.1006173","article-title":"Unsupervised extraction of epidemic syndromes from participatory influenza surveillance self-reported symptoms","volume":"15","author":"K Kalimeri","year":"2019","journal-title":"PLoS Comput Biol"},{"issue":"1","key":"pdig.0001714.ref014","doi-asserted-by":"crossref","first-page":"238","DOI":"10.1186\/s12879-017-2337-5","article-title":"Disease severity determines health-seeking behaviour amongst individuals with influenza-like illness in an internet-based cohort","volume":"17","author":"M Peppa","year":"2017","journal-title":"BMC Infect Dis"},{"issue":"3","key":"pdig.0001714.ref015","first-page":"195","article-title":"The effects of the COVID-19 pandemic on community respiratory virus 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