{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,25]],"date-time":"2026-07-25T15:21:00Z","timestamp":1784992860991,"version":"3.55.0"},"reference-count":17,"publisher":"BMJ","issue":"9","license":[{"start":{"date-parts":[[2021,4,28]],"date-time":"2021-04-28T00:00:00Z","timestamp":1619568000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/bmj.com\/coronavirus\/usage"}],"funder":[{"name":"Fundaci\u00f3n para la Investigaci\u00f3n e Innovaci\u00f3n Biom\u00e9dica del Hospital Universitario Infanta Sof\u00eda y Hospital Universitario del Henares.","award":["FHH20\/COVID05"],"award-info":[{"award-number":["FHH20\/COVID05"]}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["Occup Environ Med"],"published-print":{"date-parts":[[2021,9]]},"abstract":"<jats:sec><jats:title>Objectives<\/jats:title><jats:p>Reverse transcriptase PCR (RT-PCR) is considered the gold standard in diagnosing COVID-19. Infected healthcare workers do not go back to work until RT-PCR has demonstrated that the virus is no longer present in the upper respiratory tract. The aim of this study is to determine the most efficient time to perform RT-PCR prior to healthcare workers\u2019 reincorporation.<\/jats:p><\/jats:sec><jats:sec><jats:title>Materials and methods<\/jats:title><jats:p>This is a cohort study of healthcare workers with RT-PCR-confirmed COVID-19. Data were collected using the medical charts of healthcare workers and completed with a telephone interview. Kaplan-Meier curves were used to determine the influence of several variables on the time to RT-PCR negativisation. The impact of the variables on survival was assessed using the Breslow test. A Cox regression model was developed including the associated variables.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>159 subjects with a positive RT-PCR out of 374 workers with suspected COVID-19 were included. The median time to negativisation was 25 days from symptom onset (IQR 20\u201335 days). Presence of IgG, dyspnoea, cough and throat pain were associated with significant longer time to negativisation. Cox logistic regression was used to adjust for confounding variables. Only dyspnoea and cough remained in the model as significant determinants of prolonged negativisation time. Adjusted HRs were 0.68 (0.48\u2013096) for dyspnoea and 0.61 (0.42\u20130.88) for dry cough.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>RT-PCR during the first 3 weeks leads to a high percentage of positive results. In the presence of respiratory symptoms, negativisation took nearly 1 week more. Those who developed antibodies needed longer time to negativisate.<\/jats:p><\/jats:sec>","DOI":"10.1136\/oemed-2020-106903","type":"journal-article","created":{"date-parts":[[2021,4,28]],"date-time":"2021-04-28T18:11:14Z","timestamp":1619633474000},"page":"638-642","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":2,"title":["Survival analysis of time to SARS-CoV-2 PCR negativisation to optimise PCR prescription in health workers: the Henares COVID-19 healthcare workers cohort study"],"prefix":"10.1136","volume":"78","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8056-2630","authenticated-orcid":false,"given":"Julio","family":"Gonz\u00e1lez Martin-Moro","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marta","family":"Chamorro G\u00f3mez","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Galicia","family":"D\u00e1vila Fern\u00e1ndez","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana","family":"Elices Apellaniz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana","family":"Fern\u00e1ndez Hortelano","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Guzm\u00e1n Almagro","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angela","family":"Herranz Varela","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlos","family":"Izquierdo Rodr\u00edguez","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beatriz","family":"Molina Montes","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gema Vanesa","family":"S\u00e1nchez Moreno","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Mohedano-G\u00f3mez","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"In\u00e9s","family":"Contreras","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julio Jos\u00e9","family":"Gonz\u00e1lez L\u00f3pez","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2021,4,28]]},"reference":[{"key":"2021081710150900000_78.9.638.1","doi-asserted-by":"crossref","first-page":"100679","DOI":"10.1016\/j.nmni.2020.100679","article-title":"Novel coronavirus disease (COVID-19): a pandemic (epidemiology, pathogenesis and potential therapeutics)","volume":"35","author":"Hamid","year":"2020","journal-title":"New Microbes New Infect"},{"key":"2021081710150900000_78.9.638.2","doi-asserted-by":"publisher","DOI":"10.1002\/jmv.25678"},{"key":"2021081710150900000_78.9.638.3","doi-asserted-by":"crossref","unstructured":"Borobia AM , Carcas AJ , Arnalich F . A cohort of patients with COVID-19 in a major teaching hospital in Europe. medRxiv 2020.","DOI":"10.3390\/jcm9061733"},{"key":"2021081710150900000_78.9.638.4","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.328.7455.1507"},{"key":"2021081710150900000_78.9.638.5","doi-asserted-by":"crossref","first-page":"1540","DOI":"10.2105\/AJPH.2016.303343","article-title":"The impact of the nurses' health study on population health: prevention, translation, and control","volume":"106","author":"Colditz","year":"2016","journal-title":"Am J Public Health"},{"key":"2021081710150900000_78.9.638.6","first-page":"590","article-title":"COVID-19, negligence and occupational health and safety: ethical and legal issues for hospitals and health centres","volume":"27","author":"Freckelton","year":"2020","journal-title":"J Law Med"},{"key":"2021081710150900000_78.9.638.7","doi-asserted-by":"crossref","first-page":"2312","DOI":"10.1002\/jmv.25996","article-title":"Should RT-PCR be considered a gold standard in the diagnosis of COVID-19?","volume":"92","author":"Dram\u00e9","year":"2020","journal-title":"J Med Virol"},{"key":"2021081710150900000_78.9.638.8","doi-asserted-by":"crossref","first-page":"430","DOI":"10.5694\/mja2.50809","article-title":"Prolonged PCR positivity in health care workers with COVID-19: implications for practice guidelines","volume":"213","author":"Chua","year":"2020","journal-title":"Med J Aust"},{"key":"2021081710150900000_78.9.638.9","doi-asserted-by":"crossref","DOI":"10.2807\/1560-7917.ES.2020.25.14.2000433","article-title":"Roll-Out of SARS-CoV-2 testing for healthcare workers at a large NHS Foundation trust in the United Kingdom, March 2020","volume":"25","author":"Keeley","year":"2020","journal-title":"Euro Surveill"},{"key":"2021081710150900000_78.9.638.10","doi-asserted-by":"crossref","first-page":"237","DOI":"10.1089\/hs.2020.0036","article-title":"Respiratory protection considerations for healthcare workers during the COVID-19 pandemic","volume":"18","author":"Friese","year":"2020","journal-title":"Health Secur"},{"key":"2021081710150900000_78.9.638.11","doi-asserted-by":"publisher","DOI":"10.1016\/j.jhin.2020.04.031"},{"key":"2021081710150900000_78.9.638.12","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(20)30917-X"},{"key":"2021081710150900000_78.9.638.13","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(20)30970-3"},{"key":"2021081710150900000_78.9.638.14","first-page":"Cd013600","article-title":"Convalescent plasma or hyperimmune immunoglobulin for people with COVID-19: a rapid review","volume":"5","author":"Valk","year":"2020","journal-title":"Cochrane Database Syst Rev"},{"key":"2021081710150900000_78.9.638.15","doi-asserted-by":"crossref","first-page":"889","DOI":"10.1097\/JOM.0000000000001996","article-title":"Cycle threshold to test positivity in COVID-19 for return to work clearance in health care workers","volume":"62","author":"Domeracki","year":"2020","journal-title":"J Occup Environ Med"},{"key":"2021081710150900000_78.9.638.16","doi-asserted-by":"crossref","first-page":"2","DOI":"10.4103\/ijoem.IJOEM_53_16","article-title":"Healthy Worker Effect Phenomenon: Revisited with Emphasis on Statistical Methods - A Review","volume":"21","author":"Chowdhury","year":"2017","journal-title":"Indian J Occup Environ Med"},{"key":"2021081710150900000_78.9.638.17","doi-asserted-by":"publisher","DOI":"10.15585\/mmwr.mm6915e6"}],"container-title":["Occupational and Environmental Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/oemed-2020-106903","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,12,25]],"date-time":"2022-12-25T19:00:55Z","timestamp":1671994855000},"score":1,"resource":{"primary":{"URL":"https:\/\/oem.bmj.com\/lookup\/doi\/10.1136\/oemed-2020-106903"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,4,28]]},"references-count":17,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2021,8,17]]},"published-print":{"date-parts":[[2021,9]]}},"alternative-id":["10.1136\/oemed-2020-106903"],"URL":"https:\/\/doi.org\/10.1136\/oemed-2020-106903","relation":{},"ISSN":["1351-0711","1470-7926"],"issn-type":[{"value":"1351-0711","type":"print"},{"value":"1470-7926","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,4,28]]}}}