{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T12:02:20Z","timestamp":1781092940835,"version":"3.54.1"},"reference-count":26,"publisher":"Wiley","issue":"7","license":[{"start":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T00:00:00Z","timestamp":1774224000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T00:00:00Z","timestamp":1774224000000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["VERDI project (101045989)"],"award-info":[{"award-number":["VERDI project (101045989)"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100020655","name":"European Health and Digital Executive Agency","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100020655","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Acta Paediatrica"],"published-print":{"date-parts":[[2026,7]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Aim<\/jats:title>\n                    <jats:p>Immunocompromised children (IC) were presumed to be at higher risk of SARS\u2010COV\u20102 infection and severe COVID\u201019, but population\u2010based evidence is limited. We assessed infection risk, COVID\u201019 hospitalisation, and severe outcomes in IC compared with children with and without other high\u2010risk conditions.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a retrospective population\u2010based cohort study using electronic health registries from Italy and Norway, including children aged 1\u201314\u2009years from February 2020\u2013February 2022. Children were classified as IC, non\u2010immunocompromised with high\u2010risk conditions (non\u2010IC), or reference children (RC). Adjusted models estimated infection hospitalisation risks.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>We included 29\u2009520 children (IC\u2009=\u2009201, non\u2010IC\u2009=\u20095 144, RC\u2009=\u200924\u2009175) in Italy and 851\u2009517 (IC\u2009=\u20094 862, non\u2010IC\u2009=\u2009157\u2009358, RC\u2009=\u2009689\u2009297) in Norway. Infection rates were similar across groups in both countries. Hospitalisations were rare in both datasets; however, in the Norwegian cohort, the aHR for hospitalisation was 5.29 (95% CI: 2.49\u201311.25) for IC vs. RC and 2.30 (95% CI: 1.10\u20134.82) for IC vs. non\u2010IC. Zero and five severe cases occurred in Italy and Norway, respectively.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>IC did not have an increased risk of infection but experienced higher hospitalisation rates despite a low incidence of severe disease. This pattern may reflect precautionary clinical management rather than increased disease severity.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1111\/apa.70509","type":"journal-article","created":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T12:19:58Z","timestamp":1774268398000},"page":"1451-1460","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Risk of\n                    <scp>SARS<\/scp>\n                    \u2010\n                    <scp>CoV<\/scp>\n                    \u20102 Infection and Hospitalisation in Immunocompromised Children: A Population\u2010Based Cohort Study in Italy and Norway"],"prefix":"10.1111","volume":"115","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3586-0612","authenticated-orcid":false,"given":"Costanza Di","family":"Chiara","sequence":"first","affiliation":[{"name":"Department for Women's and Children's Health University of Padua  Padua Italy"},{"name":"Penta \u2013 Child Health Research  Padua Italy"},{"name":"Child Health Evaluative Sciences The Hospital for Sick Children  Toronto Ontario Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-8339-9485","authenticated-orcid":false,"given":"Riccardo","family":"Boracchini","sequence":"additional","affiliation":[{"name":"Department of Statistics and Quantitative Methods, Division of Biostatistics, Epidemiology and Public Health, Laboratory of Healthcare Research and Pharmacoepidemiology University of Milano\u2010Bicocca  Milan Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2794-5322","authenticated-orcid":false,"given":"Nhung T. H.","family":"Trinh","sequence":"additional","affiliation":[{"name":"PharmacoEpidemiology and Drug Safety Research Group, Department of Pharmacy, and PharmaTox Strategic Research Initiative University of Oslo  Oslo Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arianna","family":"Giugni","sequence":"additional","affiliation":[{"name":"Department of Statistics and Quantitative Methods, Division of Biostatistics, Epidemiology and Public Health, Laboratory of Healthcare Research and Pharmacoepidemiology University of Milano\u2010Bicocca  Milan Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giulia","family":"Sturniolo","sequence":"additional","affiliation":[{"name":"Department for Women's and Children's Health University of Padua  Padua Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisa","family":"Vison\u00e0","sequence":"additional","affiliation":[{"name":"Department for Women's and Children's Health University of Padua  Padua Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ali","family":"Judd","sequence":"additional","affiliation":[{"name":"Penta \u2013 Child Health Research  Padua Italy"},{"name":"Medical Research Council Clinical Trials Unit at University College London  London UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5505-9809","authenticated-orcid":false,"given":"Marthe Le","family":"Prevost","sequence":"additional","affiliation":[{"name":"Medical Research Council Clinical Trials Unit at University College London  London UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Claire","family":"Thorne","sequence":"additional","affiliation":[{"name":"University College London Great Ormond Street Institute of Child Health  London UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pia","family":"Hardelid","sequence":"additional","affiliation":[{"name":"Centre for Paediatric Epidemiology and Biostatistics, University College London Great Ormond Street Institute of Child Health  London UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlo","family":"Giaquinto","sequence":"additional","affiliation":[{"name":"Department for Women's and Children's Health University of Padua  Padua Italy"},{"name":"Penta \u2013 Child Health Research  Padua Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angela","family":"Lupattelli","sequence":"additional","affiliation":[{"name":"PharmacoEpidemiology and Drug Safety Research Group, Department of Pharmacy, and PharmaTox Strategic Research Initiative University of Oslo  Oslo Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniele","family":"Don\u00e0","sequence":"additional","affiliation":[{"name":"Department for Women's and Children's Health University of Padua  Padua Italy"},{"name":"Penta \u2013 Child Health Research  Padua Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Cantarutti","sequence":"additional","affiliation":[{"name":"Department of Statistics and Quantitative Methods, Division of Biostatistics, Epidemiology and Public Health, Laboratory of Healthcare Research and Pharmacoepidemiology University of Milano\u2010Bicocca  Milan Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,3,23]]},"reference":[{"key":"e_1_2_13_2_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00431\u2010021\u201004338\u2010y"},{"key":"e_1_2_13_3_1","doi-asserted-by":"publisher","DOI":"10.1001\/jamanetworkopen.2021.11182"},{"key":"e_1_2_13_4_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pmed.1004086"},{"key":"e_1_2_13_5_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.lana.2022.100337"},{"key":"e_1_2_13_6_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.pcl.2021.05.007"},{"key":"e_1_2_13_7_1","doi-asserted-by":"publisher","DOI":"10.15585\/mmwr.mm7116e1"},{"key":"e_1_2_13_8_1","doi-asserted-by":"publisher","DOI":"10.1097\/INF.0000000000004856"},{"key":"e_1_2_13_9_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jinf.2021.11.005"},{"key":"e_1_2_13_10_1","doi-asserted-by":"publisher","DOI":"10.2196\/44234"},{"key":"e_1_2_13_11_1","doi-asserted-by":"publisher","DOI":"10.1111\/apa.16966"},{"key":"e_1_2_13_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.vaccine.2024.04.039"},{"key":"e_1_2_13_13_1","unstructured":"DECREE\u2010LAW 24 March 2022 n. 24 Urgent provisions to overcome the measures to combat the spread of the COVID\u201019 epidemic following the end of the state of emergency. 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