{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T04:23:24Z","timestamp":1768883004119,"version":"3.49.0"},"reference-count":46,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2020,5,11]],"date-time":"2020-05-11T00:00:00Z","timestamp":1589155200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003554","name":"Lundbeckfonden","doi-asserted-by":"publisher","award":["R16-A1694"],"award-info":[{"award-number":["R16-A1694"]}],"id":[{"id":"10.13039\/501100003554","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100016342","name":"The Ministry of Health","doi-asserted-by":"publisher","award":["903516"],"award-info":[{"award-number":["903516"]}],"id":[{"id":"10.13039\/100016342","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100007398","name":"Strategiske Forskningsr\u00e5d","doi-asserted-by":"publisher","award":["0603-00280B"],"award-info":[{"award-number":["0603-00280B"]}],"id":[{"id":"10.13039\/100007398","id-type":"DOI","asserted-by":"publisher"}]},{"name":"The Capital Region Research Foundation","award":["No grant number"],"award-info":[{"award-number":["No grant number"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>Objective: Pathogenic airway bacteria colonizing the neonatal airway increase the risk of childhood asthma, but little is known about the determinants of the establishment and dynamics of the airway microbiota in early life. We studied associations between perinatal risk factors and bacterial richness of the commensal milieu in the neonatal respiratory tract. Methods: Three hundred and twenty-eight children from the Copenhagen Prospective Studies on Asthma in the Childhood2000 (COPSAC2000) at-risk birth cohort were included in this study. The bacterial richness in each of the nasopharynxes of the 1-month old, asymptomatic neonates was analyzed by use of a culture-independent technique (T-RFLP). Information on perinatal risk factors included predisposition to asthma, allergy and eczema; social status of family; maternal exposures during pregnancy; mode of delivery; and postnatal exposures. The risk factor analysis was done by conventional statistics and partial least square discriminant analysis (PLSDA). Results: The nasopharyngeal bacterial community at 1-month displayed an average of 35 (IQR: 14\u201355, range 1\u2013161) phylogenetically different bacteria groups. Season of birth was associated with nasopharyngeal bacterial richness at 1-month of age with a higher bacterial richness (p = 0.003) and more abundant specific bacterial profiles representing Gram-negative alpha-proteobacteria and Gram-positive Bacilli in the nasopharynx of summer-born children. Conclusion: Early postnatal bacterial colonization of the upper airways is significantly affected by birth season, emphasizing a future focus on the seasonality aspect in modelling the impact of early dynamic changes in airway bacterial communities in relation to later disease development.<\/jats:p>","DOI":"10.3390\/children7050045","type":"journal-article","created":{"date-parts":[[2020,5,11]],"date-time":"2020-05-11T10:01:18Z","timestamp":1589191278000},"page":"45","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Season of Birth Impacts the Neonatal Nasopharyngeal Microbiota"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5827-0885","authenticated-orcid":false,"given":"Ann-Marie Malby","family":"Schoos","sequence":"first","affiliation":[{"name":"COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Ledreborg Alle 34, 2820 Gentofte, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marie","family":"Kragh","sequence":"additional","affiliation":[{"name":"Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Lyngby, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peter","family":"Ahrens","sequence":"additional","affiliation":[{"name":"Microbiology and Infection Control, Sexually Transmitted Infections, Statens Serum Institut, 2300 Copenhagen, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Katrin Gaardbo","family":"Kuhn","sequence":"additional","affiliation":[{"name":"Microbiology and Infection Control, Sexually Transmitted Infections, Statens Serum Institut, 2300 Copenhagen, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7431-5206","authenticated-orcid":false,"given":"Morten Arendt","family":"Rasmussen","sequence":"additional","affiliation":[{"name":"COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Ledreborg Alle 34, 2820 Gentofte, Denmark"},{"name":"Faculty of Science, University of Copenhagen, 1958 Frederiksberg, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6846-6243","authenticated-orcid":false,"given":"Bo Lund","family":"Chawes","sequence":"additional","affiliation":[{"name":"COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Ledreborg Alle 34, 2820 Gentofte, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7464-7435","authenticated-orcid":false,"given":"J\u00f8rgen Skov","family":"Jensen","sequence":"additional","affiliation":[{"name":"Microbiology and Infection Control, Sexually Transmitted Infections, Statens Serum Institut, 2300 Copenhagen, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8951-6705","authenticated-orcid":false,"given":"Susanne","family":"Brix","sequence":"additional","affiliation":[{"name":"COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Ledreborg Alle 34, 2820 Gentofte, Denmark"},{"name":"Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Lyngby, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4131-7592","authenticated-orcid":false,"given":"Hans","family":"Bisgaard","sequence":"additional","affiliation":[{"name":"COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Ledreborg Alle 34, 2820 Gentofte, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jakob","family":"Stokholm","sequence":"additional","affiliation":[{"name":"COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Ledreborg Alle 34, 2820 Gentofte, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1487","DOI":"10.1056\/NEJMoa052632","article-title":"Childhood asthma after bacterial colonization of the airway in neonates","volume":"357","author":"Bisgaard","year":"2007","journal-title":"N. 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