{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,27]],"date-time":"2026-10-27T16:22:17Z","timestamp":1793118137577,"version":"4.5.0"},"reference-count":40,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,12,4]],"date-time":"2020-12-04T00:00:00Z","timestamp":1607040000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Instituto de Salud Carlos III (European Regional Development Fund &quot;Investing in your future&quot;) and Catalan Agency for the Management of Grants for University","award":["PI16\/02005 and 2017\/SGR 1342"],"award-info":[{"award-number":["PI16\/02005 and 2017\/SGR 1342"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Norovirus outbreaks frequently occur in closed or semiclosed institutions. Recent studies in Catalonia and various countries indicate that, during outbreaks in these institutions, norovirus is detected in between 23% and 60% of workers, and the prevalence of infection in asymptomatic workers involved in outbreaks ranges from 17% to 40%. In this work, we carried out a prospective study to investigate the involvement of workers in closed and semiclosed institutions during outbreaks. The attack rates (ARs) and the rate ratios (RRs) were calculated according to the type of transmission and occupational category. The RRs and 95% confidence intervals (CIs) between workers and users were calculated. The mean cycle of quantification (Cq) values were compared according to the genogroup and the presence of symptoms. ARs were higher in person-to-person transmission than in common vehicle outbreaks, and 38.8% of workers were symptomatic. The RR between workers and users was 0.46 (95% CI 0.41\u20130.52). The ARs in workers were high, particularly in workers with closer contact with users. The mean Cq was lower in patients than in asymptomatic infected persons, although the difference was only significant for genogroup I (GI). The frequency of asymptomatic infected persons suggests that personal hygiene measures should be followed by all workers in the centers affected.<\/jats:p>","DOI":"10.3390\/v12121392","type":"journal-article","created":{"date-parts":[[2020,12,7]],"date-time":"2020-12-07T12:24:39Z","timestamp":1607343879000},"page":"1392","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Involvement of Workers in Closed and Semiclosed Institutions in Outbreaks of Acute Gastroenteritis Due to Norovirus"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4875-0236","authenticated-orcid":false,"given":"Ignacio","family":"Parr\u00f3n","sequence":"first","affiliation":[{"name":"Sub-Direcci\u00f3 Regional a Barcelona del Departament de Salut, 08005 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Irene","family":"Barrabeig","sequence":"additional","affiliation":[{"name":"Sub-Direcci\u00f3 Regional a Barcelona del Departament de Salut, 08005 Barcelona, Spain"},{"name":"CIBER Epidemiologia y Salud P\u00fablica, Instituto de Salud Carlos III, 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miquel","family":"Alseda","sequence":"additional","affiliation":[{"name":"Sub-Direcci\u00f3 Regional a Lleida del Departament de Salut, 25006 Lleida, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thais","family":"Cornejo-S\u00e1nchez","sequence":"additional","affiliation":[{"name":"Departament de Microbiologia, Vall d\u2019Hebr\u00f3n Hospital, 08035 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1588-3198","authenticated-orcid":false,"given":"Susana","family":"Guix","sequence":"additional","affiliation":[{"name":"Enteric Virus Laboratory, Department of Genetics, Microbiology and Statistics, Section of Microbiology, Virology and Biotechnology, School of Biology, Institute of Nutrition and Food Safety, University of Barcelona, 08028 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1302-6723","authenticated-orcid":false,"given":"Mireia","family":"Jan\u00e9","sequence":"additional","affiliation":[{"name":"CIBER Epidemiologia y Salud P\u00fablica, Instituto de Salud Carlos III, 28029 Madrid, Spain"},{"name":"Sub-Direcci\u00f3 General de Vigil\u00e0ncia i Resposta a Emerg\u00e8ncies de Salut P\u00fablica, 08005 Barcelona, Spain"},{"name":"Departament de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Conchita","family":"Izquierdo","sequence":"additional","affiliation":[{"name":"Sub-Direcci\u00f3 General de Vigil\u00e0ncia i Resposta a Emerg\u00e8ncies de Salut P\u00fablica, 08005 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristina","family":"Rius","sequence":"additional","affiliation":[{"name":"CIBER Epidemiologia y Salud P\u00fablica, Instituto de Salud Carlos III, 28029 Madrid, Spain"},{"name":"Ag\u00e8ncia de Salut P\u00fablica de Barcelona, 08023 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0219-1907","authenticated-orcid":false,"given":"\u00c0ngela","family":"Dom\u00ednguez","sequence":"additional","affiliation":[{"name":"CIBER Epidemiologia y Salud P\u00fablica, Instituto de Salud Carlos III, 28029 Madrid, Spain"},{"name":"Departament de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"name":"the Working Group for the Study of Acute Gastroenteritis Outbreaks in Catalonia","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"607","DOI":"10.3201\/eid0505.990502","article-title":"Food-related illness and death in the United States","volume":"5","author":"Mead","year":"1999","journal-title":"Emerg. 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