{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T08:50:02Z","timestamp":1791881402780,"version":"4.3.4"},"reference-count":21,"publisher":"Wiley","issue":"11","license":[{"start":{"date-parts":[[2025,9,15]],"date-time":"2025-09-15T00:00:00Z","timestamp":1757894400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"},{"start":{"date-parts":[[2025,9,15]],"date-time":"2025-09-15T00:00:00Z","timestamp":1757894400000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Acta Paediatrica"],"published-print":{"date-parts":[[2026,11]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Aim<\/jats:title>\n                    <jats:p>The aim of this study was to investigate the possible source of laboratory\u2010confirmed pertussis in infants under 6 months of age.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This nationwide prospective study was based on laboratory\u2010confirmed cases reported in the enhanced pertussis surveillance in Sweden from 2009 to 2015. The parents or carers of 345 infants were interviewed about their clinical details including the age at onset and disease severity. They were also asked to state who had been in contact with the infant prior to onset, in order to identify possible sources of infection.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Only one possible source of infection was identified for 191 infants and the mother was presumed to be the source in 33%. These 63 cases showed different characteristics from those where a father, sibling, someone outside the immediate family or two to three people were identified as possible sources of infection. They were significantly younger, with a median of 31\u2009days of age at onset (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.01), and their hospitalisation rate (79%) was significantly higher (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.01).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Our results support general maternal vaccination against pertussis. Other preventive measures also need to be strengthened and implemented to prevent severe pertussis disease in the youngest infants with higher risk of death.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1111\/apa.70300","type":"journal-article","created":{"date-parts":[[2025,9,15]],"date-time":"2025-09-15T12:05:53Z","timestamp":1757937953000},"page":"2566-2571","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Swedish Infants Developed Pertussis at a Younger Age if Their Mother Was the Possible Source of Infection in 2009\u20132015"],"prefix":"10.1111","volume":"115","author":[{"given":"Bernice","family":"Aronsson","sequence":"first","affiliation":[{"name":"The Public Health Agency of Sweden  Stockholm Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5680-6367","authenticated-orcid":false,"given":"Lennart","family":"Nilsson","sequence":"additional","affiliation":[{"name":"Department of Paediatrics Region J\u00f6nk\u00f6ping County  J\u00f6nk\u00f6ping Sweden"},{"name":"Department of Biomedical and Clinical Sciences Link\u00f6ping University  Link\u00f6ping Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jann","family":"Storsaeter","sequence":"additional","affiliation":[{"name":"The Public Health Agency of Sweden  Stockholm Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Henrik","family":"K\u00e4llberg","sequence":"additional","affiliation":[{"name":"The Public Health Agency of Sweden  Stockholm Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7058-2419","authenticated-orcid":false,"given":"Emma","family":"Appelqvist","sequence":"additional","affiliation":[{"name":"The Public Health Agency of Sweden  Stockholm Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2025,9,15]]},"reference":[{"key":"e_1_2_10_2_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12879\u2010020\u201005535\u20100"},{"key":"e_1_2_10_3_1","doi-asserted-by":"publisher","DOI":"10.1128\/cmr.18.2.326\u2010382.2005"},{"key":"e_1_2_10_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.vaccine.2009.07.092"},{"key":"e_1_2_10_5_1","unstructured":"Folkh\u00e4lsomyndigheten \u201c22nd Annual Report. Pertussis Surveillance in Sweden \u201d (2020)."},{"key":"e_1_2_10_6_1","unstructured":"Folkh\u00e4lsomyndigheten \u201cPertussis Surveillance in Sweden\u201423rd Annual Report \u201d (2022)."},{"key":"e_1_2_10_7_1","doi-asserted-by":"publisher","DOI":"10.2807\/esm.11.05.00626-en"},{"key":"e_1_2_10_8_1","doi-asserted-by":"publisher","DOI":"10.2807\/1560\u20107917.es2015.20.6.21032"},{"key":"e_1_2_10_9_1","volume-title":"R: A Language and Environment for Statistical Computing","author":"R Core Team","year":"2023"},{"key":"e_1_2_10_10_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2015\u20101120"},{"key":"e_1_2_10_11_1","doi-asserted-by":"publisher","DOI":"10.1086\/652281"},{"key":"e_1_2_10_12_1","doi-asserted-by":"publisher","DOI":"10.1097\/inf.0000000000001378"},{"key":"e_1_2_10_13_1","doi-asserted-by":"publisher","DOI":"10.1097\/01.inf.0000258699.64164.6d"},{"key":"e_1_2_10_14_1","doi-asserted-by":"publisher","DOI":"10.2807\/1560\u20107917.Es.2021.26.4.1900762"},{"issue":"3","key":"e_1_2_10_15_1","doi-asserted-by":"crossref","first-page":"E195","DOI":"10.33321\/cdi.2014.38.35","article-title":"Finding the \u2018Who\u2019 in Whooping Cough: Vaccinated Siblings Are Important Pertussis Sources in Infants 6 Months of Age and Under","volume":"38","author":"Bertilone C.","year":"2014","journal-title":"Communicable Diseases Intelligence Quarterly Report"},{"key":"e_1_2_10_16_1","doi-asserted-by":"publisher","DOI":"10.1093\/jpids\/piy128"},{"key":"e_1_2_10_17_1","doi-asserted-by":"publisher","DOI":"10.1093\/cid\/civ472"},{"issue":"35","key":"e_1_2_10_18_1","first-page":"433","article-title":"Pertussis Vaccines: WHO Position Paper\u2014August 2015","volume":"90","author":"World Health Organization","year":"2015","journal-title":"Weekly Epidemiological Record"},{"key":"e_1_2_10_19_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.immuni.2017.03.009"},{"key":"e_1_2_10_20_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.vaccine.2011.10.089"},{"key":"e_1_2_10_21_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.100.6.e10"},{"key":"e_1_2_10_22_1","unstructured":"Folkh\u00e4lsomyndigheten \u201cRekommendation om Vaccination Mot Kikhosta f\u00f6r Gravida [Recommendation of maternal pertussis vaccination] \u201d (2022) https:\/\/www.folkhalsomyndigheten.se\/contentassets\/4a9ad8ce7bd243779f9c86053fbbafbd\/rekommendation\u2010vaccination\u2010kikhosta\u2010gravida.pdf."}],"container-title":["Acta Paediatrica"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/apa.70300","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1111\/apa.70300","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/apa.70300","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T08:17:00Z","timestamp":1791879420000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/apa.70300"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,9,15]]},"references-count":21,"journal-issue":{"issue":"11","published-print":{"date-parts":[[2026,11]]}},"alternative-id":["10.1111\/apa.70300"],"URL":"https:\/\/doi.org\/10.1111\/apa.70300","archive":["Portico"],"relation":{},"ISSN":["0803-5253","1651-2227"],"issn-type":[{"value":"0803-5253","type":"print"},{"value":"1651-2227","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,9,15]]},"assertion":[{"value":"2023-12-14","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-09-03","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-09-15","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}