{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,7]],"date-time":"2026-06-07T14:59:10Z","timestamp":1780844350325,"version":"3.54.1"},"reference-count":46,"publisher":"BMJ","issue":"6","license":[{"start":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T00:00:00Z","timestamp":1780617600000},"content-version":"unspecified","delay-in-days":4,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2026,4,30]]},"published-print":{"date-parts":[[2026,6]]},"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>A proportion of patients hospitalised for COVID-19 acquire the disease during their hospital stay, underscoring the risk of hospital-acquired COVID-19 (HA-COVID-19). This risk is presumed to be high, given how commonly and intensely air and surfaces within hospitals are reportedly contaminated with SARS-CoV-2. However, the true extent of HA-COVID-19 worldwide remains unknown, with limited understanding of factors that influence its occurrence and how these have evolved over time. This review will therefore aim to estimate the pooled prevalence of HA-COVID-19 among hospitalised COVID-19 patients globally and investigate differences by country, type of hospitals, medical specialty, length and timing of studied periods.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods and analysis<\/jats:title>\n                    <jats:p>A systematic review and meta-analysis will be conducted adhering to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. MEDLINE and PubMed Central (via PubMed), Scopus, Embase (via Ovid), the Web of Science Core Collection as well as websites of public health agencies (PHA) will be searched until 1 July 2026. All journal articles and sources from PHAs reporting any primary data on the prevalence of HA-COVID-19 will be included. Methodological quality will be assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data. The primary outcome will be the global prevalence of HA-COVID-19. Data synthesis will include random-effects proportional meta-analysis. Estimates will be presented with two-sided 95% CIs and heterogeneity assessed using the I\u00b2 statistic.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Ethics and dissemination<\/jats:title>\n                    <jats:p>Ethical approval is not needed as no original data will be generated. This review will be published in an international, peer-reviewed journal.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>PROSPERO registration number<\/jats:title>\n                    <jats:p>CRD420251136884.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2025-113205","type":"journal-article","created":{"date-parts":[[2026,6,7]],"date-time":"2026-06-07T14:25:15Z","timestamp":1780842315000},"page":"e113205","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Global prevalence and determinants of hospital-acquired COVID-19: protocol for a systematic review and meta-analysis"],"prefix":"10.1136","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5234-2788","authenticated-orcid":false,"given":"Noach Leon","family":"Ribaric","sequence":"first","affiliation":[{"name":"Faculty of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany"},{"name":"Institute of Medical Biometry and Epidemiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany"},{"name":"School of Engineering, University of Edinburgh, Edinburgh, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-5602-6685","authenticated-orcid":false,"given":"Zixue","family":"O\u2019Neill-Byrne","sequence":"additional","affiliation":[{"name":"School of Engineering, University of Edinburgh, Edinburgh, UK"},{"name":"Edinburgh Medical School, University of Edinburgh, Edinburgh, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Achim","family":"Hellinger","sequence":"additional","affiliation":[{"name":"Department of General, Visceral, Endocrine and Oncologic Surgery, University Medicine Marburg, Fulda, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Pan","sequence":"additional","affiliation":[{"name":"Development Centre for Population Health, University of Leicester, Leicester, UK"},{"name":"Department of Infectious Diseases and HIV Medicine, University Hospitals of Leicester NHS Trust, Leicester, UK"},{"name":"Division of Public Health and Epidemiology, University of Leicester, Leicester, UK"},{"name":"Leicester NIHR Biomedical Research Centre, Leicester, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nick M","family":"Wilson","sequence":"additional","affiliation":[{"name":"School of Engineering, University of Edinburgh, Edinburgh, UK"},{"name":"Department of Anaesthesia and Critical Care, Royal Infirmary of Edinburgh, Edinburgh, Scotland, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ignazio Maria","family":"Viola","sequence":"additional","affiliation":[{"name":"School of Engineering, University of Edinburgh, Edinburgh, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Timothy S","family":"Walsh","sequence":"additional","affiliation":[{"name":"Usher Institute for Population Health Sciences, University of Edinburgh, Edinburgh, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tom","family":"Lawton","sequence":"additional","affiliation":[{"name":"Improvement Academy, Bradford Institute for Health Research, Bradford Royal Infirmary, Bradford, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sergejs","family":"Afanasjevs","sequence":"additional","affiliation":[{"name":"School of Engineering, University of Edinburgh, Edinburgh, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Clementina","family":"Calabria","sequence":"additional","affiliation":[{"name":"Department of Anaesthesia and Critical Care, Royal Infirmary of Edinburgh, Edinburgh, Scotland, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Federico","family":"De Angelis","sequence":"additional","affiliation":[{"name":"Roslin Institute, University of Edinburgh, Edinburgh, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas Theo","family":"Brehm","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, I. 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