{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T11:23:55Z","timestamp":1787657035460,"version":"build-2736575974"},"reference-count":31,"publisher":"BMJ","issue":"3","license":[{"start":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T00:00:00Z","timestamp":1787616000000},"content-version":"unspecified","delay-in-days":55,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"name":"Dr. Thorvald Madsens Legat","award":["Not applicable"],"award-info":[{"award-number":["Not applicable"]}]},{"DOI":"10.13039\/501100009418","name":"Nordsj\u00e6llands Hospital","doi-asserted-by":"publisher","award":["Not Applicable"],"award-info":[{"award-number":["Not Applicable"]}],"id":[{"id":"10.13039\/501100009418","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["bmjph"],"accepted":{"date-parts":[[2026,8,5]]},"published-print":{"date-parts":[[2026,7]]},"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>This study examined whether ending oral poliovirus vaccination (OPV) increased enterovirus (EV) associated hospitalizations in children. Inactivated poliovirus vaccination (IPV) protects against disease caused by poliovirus. In contrast to OPV, it does not provoke a mucosal defence. Therefore, it is hypothesised that IPV does not offer cross-protection against other EV infections.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>The prevalence and incidence of EV cases were estimated in three cohorts of Danish children. To address the historically sparse diagnosis and registration of EV, we trained supervised machine-learning models in 2017\u20132018\u2009admission data, validated them against the 2015\u20132016\u2009cohort and applied the final model to the period 1996\u20132014. The study was conducted using nation-wide Danish registries on hospital admissions in 1996\u20132018. Three cohorts of all children living in Denmark born between 1 January 1996 and 31 December 1998 (201 460 live births), 1 January 2000 and 31 December 2004 (325 825 live births) and between 1 January 2005 and 31 December 2007 (194 303 live births) were followed in hospital registers until age 12. The outcomes were the prevalence and incidence of EV cases in the three cohorts and the ratio of estimates between the OPV and IPV cohorts.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among 201\u2009460 live births in the OPV cohort, 178\u2009EV cases were identified, corresponding to an incidence rate of 6.48 per 100\u2009000 risk years. The incidence rates per 100\u2009000 risk years were 10.64 and 13.81 in the IPV cohorts, with 460 and 326\u2009EV cases, respectively. The incidence rate ratio was 1.64 (95% CI 1.38 to 1.95) and 2.13 (1.78 to 2.56) in the two IPV cohorts compared with the OPV cohort.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Children born in Denmark after 2001 had significantly higher rates of EV-related hospitalisations, suggesting potential cross-protective effects of OPV for EV-related hospitalisations. While supporting the hypothesis, the results should not be seen as risk attribution estimates, as the residual impact of diagnostic improvements is unmeasured.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjph-2026-005241","type":"journal-article","created":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T11:10:16Z","timestamp":1787656216000},"page":"e005241","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Changed frequency of enterovirus hospitalisations after change of polio vaccination scheme: a nation-wide cohort study from Denmark"],"prefix":"10.1136","volume":"4","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6503-5632","authenticated-orcid":false,"given":"Caroline Klint","family":"Johannesen","sequence":"first","affiliation":[{"name":"Department of Clinical Research, Nordsj\u00e6llands Hospital, Hiller\u00f8d, Capital Region of Denmark, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Neil Alexandre","family":"Scheidwasser","sequence":"additional","affiliation":[{"name":"Section of Health Data Science and AI, Department of Public Health, University of Copenhagen Faculty of Health and Medical Sciences, Copenhagen, Capital Region of Denmark, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6807-8347","authenticated-orcid":false,"given":"Theis","family":"Lange","sequence":"additional","affiliation":[{"name":"Department of Public Health, University of Copenhagen Faculty of Health and Medical Sciences, Copenhagen, Capital Region of Denmark, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6286-5999","authenticated-orcid":false,"given":"Tyra G","family":"Krause","sequence":"additional","affiliation":[{"name":"Epidemiological Infectious Disease Preparedness, Statens Serum Institut, Copenhagen, Capital Region of Denmark, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thea K","family":"Fischer","sequence":"additional","affiliation":[{"name":"Department of Clinical Research, Nordsj\u00e6llands Hospital, Hiller\u00f8d, Capital Region of Denmark, Denmark"},{"name":"Department of Public Health, University of Copenhagen Faculty of Health and Medical Sciences, Copenhagen, Capital Region of Denmark, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,8,25]]},"reference":[{"key":"2026082504101326000_4.3.e005241.1","doi-asserted-by":"crossref","first-page":"25","DOI":"10.3201\/eid2501.181089","article-title":"Enterovirus A71 Infection and Neurologic Disease, Madrid, Spain, 2016","volume":"25","author":"Taravilla","year":"2019","journal-title":"Emerg Infect Dis"},{"key":"2026082504101326000_4.3.e005241.2","doi-asserted-by":"crossref","first-page":"2300313","DOI":"10.2807\/1560-7917.ES.2023.28.39.2300313","article-title":"Increased reports of severe myocarditis associated with enterovirus infection in neonates, United Kingdom, 27 June 2022 to 26 April 2023","volume":"28","author":"Singanayagam","year":"2023","journal-title":"Eurosurveillance"},{"key":"2026082504101326000_4.3.e005241.3","doi-asserted-by":"crossref","DOI":"10.2807\/1560-7917.ES2014.19.44.20952","article-title":"Acute flaccid paralysis following enterovirus D68 associated pneumonia, France, 2014","volume":"19","author":"Lang","year":"2014","journal-title":"Euro Surveill"},{"key":"2026082504101326000_4.3.e005241.4","doi-asserted-by":"publisher","DOI":"10.1097\/INF.0000000000002188"},{"key":"2026082504101326000_4.3.e005241.5","doi-asserted-by":"crossref","DOI":"10.2807\/1560-7917.ES.2018.23.44.1800537","article-title":"Upsurge in echovirus 30 detections in five EU\/EEA countries, April to September, 2018","volume":"23","author":"Broberg","year":"2018","journal-title":"Euro Surveill"},{"key":"2026082504101326000_4.3.e005241.6","doi-asserted-by":"publisher","DOI":"10.4161\/hv.27087"},{"key":"2026082504101326000_4.3.e005241.7","doi-asserted-by":"crossref","unstructured":"Minor PD . 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