{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,7,16]],"date-time":"2025-07-16T12:54:42Z","timestamp":1752670482613,"version":"3.37.3"},"reference-count":27,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2023,9,28]],"date-time":"2023-09-28T00:00:00Z","timestamp":1695859200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2023,9,28]],"date-time":"2023-09-28T00:00:00Z","timestamp":1695859200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia,Portugal","award":["UIDB\/04750\/2020  and LA\/P\/0064\/2020","UIDB\/04750\/2020  and LA\/P\/0064\/2020","UIDB\/04750\/2020  and LA\/P\/0064\/2020","UIDB\/04750\/2020  and LA\/P\/0064\/2020","UIDB\/04750\/2020  and LA\/P\/0064\/2020"],"award-info":[{"award-number":["UIDB\/04750\/2020  and LA\/P\/0064\/2020","UIDB\/04750\/2020  and LA\/P\/0064\/2020","UIDB\/04750\/2020  and LA\/P\/0064\/2020","UIDB\/04750\/2020  and LA\/P\/0064\/2020","UIDB\/04750\/2020  and LA\/P\/0064\/2020"]}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["CEECIND\/02386\/2018"],"award-info":[{"award-number":["CEECIND\/02386\/2018"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Sci Rep"],"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Since the beginning of the pandemic, there has been a great deal of controversy regarding the role of schools in the spread of SARS-CoV-2 infection, and the relative contribution of students, teachers, and others. To quantify the clustering effect of SARS-CoV-2 infection within classes and schools considering the seroprevalence of specific antibodies among students and school staff (teachers and non-teachers) evaluated in schools located in the Northern region of Portugal. 1517 individuals (1307 students and 210 school staff) from 4 public and 2 private schools, comprising daycare to secondary levels, were evaluated. A rapid point-of-care test for SARS-CoV-2 specific IgM and IgG antibodies was performed and a questionnaire was completed providing sociodemographic and clinical information. We calculated the seroprevalence of IgM and IgG antibodies and estimated the Median Odds Ratio (OR) and 95% confidence interval (CI) to assess the clustering effect, using a multilevel (school and class) logistic regression. SARS-CoV-2 seroprevalence (IgM or IgG) was 21.8% and 23.8% (<jats:italic>p<\/jats:italic>\u2009=\u20090.575) in students and school staff, respectively. A total of 84 (8.6%) students and 35 (16.7%) school staff reported a previous molecular diagnosis. Among students, those who reported high-risk contacts only at school (OR\u2009=\u20091.13; 95% CI 0.72\u20131.78) had a seroprevalence similar to those without high-risk contacts; however, seroprevalence was significantly higher among those who only reported a high-risk contact outside the school (OR\u2009=\u20096.56; 95% CI 3.68\u201311.72), or in both places (OR\u2009=\u20097.83; 95% CI 5.14\u201311.93). Similar associations were found for school staff. The median OR was 1.00 (95% CI 1.00, 1.38) at the school-level and 1.78 (95% CI 1.40, 2.06) at the class-level. SARS-CoV-2 seroprevalence was similar between students and staff, without a clustering effect observed at the school level, and only a moderate clustering effect documented within classes. These results indicate that the mitigation measures in the school environment can prevent the spread of class outbreaks to the remaining school community.<\/jats:p>","DOI":"10.1038\/s41598-023-42470-x","type":"journal-article","created":{"date-parts":[[2023,9,28]],"date-time":"2023-09-28T09:01:49Z","timestamp":1695891709000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Measuring the clustering effect of the SARS-CoV-2 transmission in a school population: a cross-sectional study in a high incidence region"],"prefix":"10.1038","volume":"13","author":[{"given":"Milton","family":"Severo","sequence":"first","affiliation":[]},{"given":"Paula","family":"Meireles","sequence":"additional","affiliation":[]},{"given":"Ana Isabel","family":"Ribeiro","sequence":"additional","affiliation":[]},{"given":"V\u00edtor","family":"Morais","sequence":"additional","affiliation":[]},{"given":"Henrique","family":"Barros","sequence":"additional","affiliation":[]}],"member":"297","published-online":{"date-parts":[[2023,9,28]]},"reference":[{"issue":"8","key":"42470_CR1","doi-asserted-by":"publisher","first-page":"727","DOI":"10.1056\/NEJMoa2001017","volume":"382","author":"N Zhu","year":"2020","unstructured":"Zhu, N. et al. A novel coronavirus from patients with pneumonia in China, 2019. N. Engl. J. Med. 382(8), 727\u2013733 (2020).","journal-title":"N. Engl. J. Med."},{"key":"42470_CR2","unstructured":"UNESCO. Adverse consequences of school closures 2021. Available from: https:\/\/en.unesco.org\/covid19\/educationresponse\/consequences."},{"issue":"5","key":"42470_CR3","doi-asserted-by":"publisher","first-page":"397","DOI":"10.1016\/S2352-4642(20)30095-X","volume":"4","author":"RM Viner","year":"2020","unstructured":"Viner, R. M. et al. School closure and management practices during coronavirus outbreaks including COVID-19: A rapid systematic review. Lancet Child Adolesc. Health 4(5), 397\u2013404 (2020).","journal-title":"Lancet Child Adolesc. Health"},{"issue":"9","key":"42470_CR4","doi-asserted-by":"publisher","first-page":"644","DOI":"10.1093\/aje\/kww083","volume":"184","author":"C Jackson","year":"2016","unstructured":"Jackson, C., Vynnycky, E. & Mangtani, P. The relationship between school holidays and transmission of influenza in England and wales. Am. J. Epidemiol. 184(9), 644\u2013651 (2016).","journal-title":"Am. J. Epidemiol."},{"issue":"2","key":"42470_CR5","doi-asserted-by":"publisher","first-page":"103","DOI":"10.1016\/j.epidem.2011.03.003","volume":"3","author":"KT Eames","year":"2011","unstructured":"Eames, K. T., Tilston, N. L. & Edmunds, W. J. The impact of school holidays on the social mixing patterns of school children. Epidemics 3(2), 103\u2013108 (2011).","journal-title":"Epidemics"},{"issue":"5","key":"42470_CR6","doi-asserted-by":"publisher","first-page":"e243","DOI":"10.1016\/S2468-2667(20)30084-0","volume":"5","author":"W Van Lancker","year":"2020","unstructured":"Van Lancker, W. & Parolin, Z. COVID-19, school closures, and child poverty: A social crisis in the making. 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