{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:24:50Z","timestamp":1760145890245,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2024,9,5]],"date-time":"2024-09-05T00:00:00Z","timestamp":1725494400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/04750\/2020","LA\/P\/0064\/2020"],"award-info":[{"award-number":["UIDB\/04750\/2020","LA\/P\/0064\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Objective: Knowledge of the role of hospital conditions in SARS-CoV-2 transmission should inform strategies for the prevention of nosocomial spread of this pathogen and of similarly transmitted viruses. This study aimed to identify risk factors for nosocomial acquisition of SARS-CoV-2. Methods: We ran a nested case-control study with incidence density sampling among adult patients hospitalized for &gt;7 days (August\u2013December 2020). Patients testing positive for SARS-CoV-2 after the 7th day of hospitalization were defined as cases and matched with controls (1:4) by date of admission, hospitalization duration until index date, and type of department. Individual and contextual characteristics were gathered, including admission characteristics and exposures during the risk period. Conditional logistic regression was used to estimate the odds ratios (ORs) with respective 95% confidence intervals (CI) separately for probable (diagnosed on day 8\u201313) and definitive (diagnosed after day 14) nosocomial sets. Results: We identified 65 cases (31 probable; 34 definitive) and 219 controls. No individual characteristic was related to nosocomial acquisition of SARS-CoV-2. Contextual risk factors for nosocomial acquisition were staying in a non-refurbished room (probable nosocomial: OR = 3.6, 1.18\u201310.87), contact with roommates with newly diagnosed SARS-CoV-2 (probable nosocomial: OR = 9.9, 2.11\u201346.55; definitive nosocomial: OR = 3.4, 1.09\u201310.30), and contact with roommates with a first positive test 21\u201390 days before the beginning of contact (probable nosocomial: OR = 10.7, 1.97\u201357.7). Conclusions: Hospital conditions and contact with recently infected patients modulated nosocomial SARS-CoV-2 transmission. These results alert us to the importance of the physical context and of agile screening procedures to shorten contact with patients with recent infection.<\/jats:p>","DOI":"10.3390\/jcm13175251","type":"journal-article","created":{"date-parts":[[2024,9,5]],"date-time":"2024-09-05T02:34:06Z","timestamp":1725503646000},"page":"5251","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Contextual Hospital Conditions and the Risk of Nosocomial SARS-CoV-2 Infection: A Matched Case-Control Study with Density Sampling in a Large Portuguese Hospital"],"prefix":"10.3390","volume":"13","author":[{"given":"Francisco","family":"Almeida","sequence":"first","affiliation":[{"name":"Unidade de Preven\u00e7\u00e3o e Controlo de Infe\u00e7\u00e3o e Resist\u00eancia aos Antimicrobianos, Centro de Epidemiologia Hospitalar, Centro Hospitalar de S\u00e3o Jo\u00e3o, 4200-319 Porto, Portugal"},{"name":"Departamento de Ci\u00eancias da Sa\u00fade P\u00fablica e Forenses e Educa\u00e7\u00e3o M\u00e9dica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"},{"name":"EPIUnit, Instituto de Sa\u00fade P\u00fablica da Universidade do Porto, 4200-319 Porto, Portugal"},{"name":"Laborat\u00f3rio Para a Investiga\u00e7\u00e3o Integrativa e Translacional em Sa\u00fade Populacional (ITR), Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Sofia","family":"Correia","sequence":"additional","affiliation":[{"name":"EPIUnit, Instituto de Sa\u00fade P\u00fablica da Universidade do Porto, 4200-319 Porto, Portugal"},{"name":"Laborat\u00f3rio Para a Investiga\u00e7\u00e3o Integrativa e Translacional em Sa\u00fade Populacional (ITR), Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"C\u00e1tia","family":"Leal","sequence":"additional","affiliation":[{"name":"EPIUnit, Instituto de Sa\u00fade P\u00fablica da Universidade do Porto, 4200-319 Porto, Portugal"},{"name":"Laborat\u00f3rio Para a Investiga\u00e7\u00e3o Integrativa e Translacional em Sa\u00fade Populacional (ITR), Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Mariana","family":"Guedes","sequence":"additional","affiliation":[{"name":"Unidade de Preven\u00e7\u00e3o e Controlo de Infe\u00e7\u00e3o e Resist\u00eancia aos Antimicrobianos, Centro de Epidemiologia Hospitalar, Centro Hospitalar de S\u00e3o Jo\u00e3o, 4200-319 Porto, Portugal"},{"name":"Infectious Diseases and Microbiology Division, Hospital Universitario Virgen Macarena, Department of Medicine, Biomedicine Institute of Sevilla (IBiS)\/CSIC, University of Sevilla, 41004 Sevilla, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7218-8004","authenticated-orcid":false,"given":"Raquel","family":"Duro","sequence":"additional","affiliation":[{"name":"Unidade Local do Programa de Controlo de Infe\u00e7\u00e3o e Resist\u00eancia aos Antimicrobianos, Unidade Local de Sa\u00fade do T\u00e2mega e Sousa, 4560-136 Penafiel, Portugal"},{"name":"Servi\u00e7o de Doen\u00e7as Infeciosas, Unidade Local de Sa\u00fade do T\u00e2mega e Sousa, 4560-136 Penafiel, Portugal"}]},{"given":"Paulo","family":"Andrade","sequence":"additional","affiliation":[{"name":"Unidade de Preven\u00e7\u00e3o e Controlo de Infe\u00e7\u00e3o e Resist\u00eancia aos Antimicrobianos, Centro de Epidemiologia Hospitalar, Centro Hospitalar de S\u00e3o Jo\u00e3o, 4200-319 Porto, Portugal"},{"name":"Servi\u00e7o de Doen\u00e7as Infeciosas, Centro Hospitalar de S\u00e3o Jo\u00e3o, 4200-319 Porto, Portugal"}]},{"given":"Afonso","family":"Pedrosa","sequence":"additional","affiliation":[{"name":"Servi\u00e7o de Intelig\u00eancia de Dados, Centro Hospitalar Universit\u00e1rio S\u00e3o Jo\u00e3o, 4200-319 Porto, Portugal"}]},{"given":"Nuno","family":"Rocha-Pereira","sequence":"additional","affiliation":[{"name":"Unidade de Preven\u00e7\u00e3o e Controlo de Infe\u00e7\u00e3o e Resist\u00eancia aos Antimicrobianos, Centro de Epidemiologia Hospitalar, Centro Hospitalar de S\u00e3o Jo\u00e3o, 4200-319 Porto, Portugal"},{"name":"Departamento de Medicina, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Carlos","family":"Lima-Alves","sequence":"additional","affiliation":[{"name":"Unidade de Preven\u00e7\u00e3o e Controlo de Infe\u00e7\u00e3o e Resist\u00eancia aos Antimicrobianos, Centro de Epidemiologia Hospitalar, Centro Hospitalar de S\u00e3o Jo\u00e3o, 4200-319 Porto, Portugal"},{"name":"INFARMED\u2014Autoridade Nacional do Medicamento e Produtos de Sa\u00fade, I.P., 1749-004 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7368-9609","authenticated-orcid":false,"given":"Ana","family":"Azevedo","sequence":"additional","affiliation":[{"name":"Departamento de Ci\u00eancias da Sa\u00fade P\u00fablica e Forenses e Educa\u00e7\u00e3o M\u00e9dica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"},{"name":"EPIUnit, Instituto de Sa\u00fade P\u00fablica da Universidade do Porto, 4200-319 Porto, Portugal"},{"name":"Laborat\u00f3rio Para a Investiga\u00e7\u00e3o Integrativa e Translacional em Sa\u00fade Populacional (ITR), Universidade do Porto, 4200-319 Porto, Portugal"},{"name":"Centro de Epidemiologia Hospitalar, Centro Hospitalar Universit\u00e1rio S\u00e3o Jo\u00e3o, 4200-319 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e2020498","DOI":"10.1001\/jamanetworkopen.2020.20498","article-title":"Incidence of Nosocomial COVID-19 in Patients Hospitalized at a Large US Academic Medical Center","volume":"3","author":"Rhee","year":"2020","journal-title":"JAMA Netw. 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