{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T18:15:28Z","timestamp":1783620928557,"version":"3.55.0"},"reference-count":15,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T00:00:00Z","timestamp":1783555200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Institute for Health and Care Research (NIHR) Health Protection Research Unit (HPRU) in Respiratory Infections, Imperial College London, Imperial College London","award":["NIHR200927"],"award-info":[{"award-number":["NIHR200927"]}]},{"name":"National Institute for Health and Care Research (NIHR) Health Protection Research Unit (HPRU) in Respiratory Infections, Imperial College London, Imperial College London","award":["NIHR207417"],"award-info":[{"award-number":["NIHR207417"]}]},{"name":"UK Health Security Agency and Medical Research Council","award":["MR\/X004058\/1"],"award-info":[{"award-number":["MR\/X004058\/1"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>Full blood count (FBC) provides a range of cellular haematological parameters and serves as a routinely available basic immune profile. While FBC has been widely used to monitor moderate-to-severe COVID-19 in hospitalised settings, its temporal dynamics in mild, community-managed cases remain poorly characterised, despite these constituting the majority of global infections.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In a prospective cohort study, we tracked the cellular haematological profiles of 93 recently exposed, immunologically na\u00efve individuals with mild COVID-19 and no underlying co-morbidities, recruited to the Integrated Network for Surveillance, Trials and Investigations into COVID-19 Transmission (INSTINCT) study. Blood samples were collected on D0, D7, D14 and D28 and subsequently aligned to infection-timepoints based on the day of first detected PCR positivity, and analysed using mixed-effects models.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Over 30% of cases exhibited transient, clinically defined neutropenia (mean (95% CI): First PCR-Positive (FP) 2.47x10\n                      <jats:sup>9<\/jats:sup>\n                      \/L (2.26\u20132.68) vs convalescence 3.34 x10\n                      <jats:sup>9<\/jats:sup>\n                      \/L (2.98\u20133.7); p\u2009=\u20090.0013). Over 20% exhibited lymphopenia (FP 1.38x10\n                      <jats:sup>9<\/jats:sup>\n                      \/L (1.28\u20131.48) vs convalescence 1.79x10\n                      <jats:sup>9<\/jats:sup>\n                      \/L (1.79\u20132.01); p\u2009=\u20090.0013). Additionally, we observed a notable elevation in platelet count, peaking approximately two weeks after initial infection (mean (95% CI): FP\u2009+\u200914 283x10\n                      <jats:sup>9<\/jats:sup>\n                      \/L (254\u2013311) vs convalescence 237x10\n                      <jats:sup>9<\/jats:sup>\n                      \/L (222\u2013252); p\u2009=\u20090.0013).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Transient neutropenia and lymphopenia occurred in approximately one-third and one-fifth of mild COVID-19 cases, respectively, and were followed by a delayed increase in platelet count. This study provides a descriptive, prospective dataset of full blood count parameters spanning early infection to convalescence in immunologically na\u00efve individuals with mild SARS-CoV-2 infection. These data may support mathematical modelling of within-host cellular haematological dynamics and have potential clinical relevance for understanding typical trajectories of routine blood parameters during mild disease.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0353142","type":"journal-article","created":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T17:29:18Z","timestamp":1783618158000},"page":"e0353142","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Full blood count dynamics in immunologically na\u00efve individuals with mild COVID-19: A prospective community cohort study"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0554-339X","authenticated-orcid":true,"given":"Seran","family":"Hakki","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sean","family":"Nevin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emily","family":"Conibear","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kieran J.","family":"Madon","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joe","family":"Fenn","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jakob","family":"Jonnerby","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nieves","family":"Derqui","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aleksandra","family":"Koycheva","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rhia","family":"Kundu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5302-7563","authenticated-orcid":true,"given":"Hamish","family":"Houston","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Timesh D.","family":"Pillay","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra L.","family":"Kondratiuk","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Janakan Sam","family":"Narean","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kimone L.","family":"Fisher","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Varro","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Constanta","family":"Luca","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samuel","family":"Evetts","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter","family":"Kelleher","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Onn Min","family":"Kon","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3773-2390","authenticated-orcid":true,"given":"Graham P.","family":"Taylor","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ajit","family":"Lalvani","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,7,9]]},"reference":[{"issue":"1","key":"pone.0353142.ref001","doi-asserted-by":"crossref","first-page":"574","DOI":"10.1186\/s12879-021-06277-3","article-title":"Correlation between white blood cell count at admission and mortality in COVID-19 patients: A retrospective study","volume":"21","author":"B Zhu","year":"2021","journal-title":"BMC Infect Dis"},{"issue":"1","key":"pone.0353142.ref002","doi-asserted-by":"crossref","first-page":"9361","DOI":"10.1038\/s41598-021-88679-6","article-title":"The COVID-19 lab score: An accurate dynamic tool to predict in-hospital outcomes in COVID-19 patients","volume":"11","author":"PJ Antunez Mui\u00f1os","year":"2021","journal-title":"Sci 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