{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T01:41:18Z","timestamp":1792806078306,"version":"4.5.0"},"reference-count":100,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2023,8,2]],"date-time":"2023-08-02T00:00:00Z","timestamp":1690934400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Human Resources Development Operational Program 2014-2020, financed from the European Social Fund","award":["62487\/03.06.2022 POCU 993\/6\/13\/\u2014"],"award-info":[{"award-number":["62487\/03.06.2022 POCU 993\/6\/13\/\u2014"]}],"id":[{"id":"https:\/\/ror.org\/048snh465","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Acute respiratory tract infections (ARTIs) are one of the main reasons that the pediatric population goes to the doctor. The connection between ARTI and vitamin D (VD) is currently debated by the medical community, and so far, there has been little agreement with regard to the ideal level of 25(OH)D concentration that would provide protection for the respiratory tract, or the effectiveness of its administration in the treatment of respiratory infections. The purpose of this literature review was to bring attention to the immunomodulatory and antiviral function of vitamin D and its relation to the respiratory system by examining the main ARTIs, including SARS-CoV-2. The latter has affected the pediatric population in different ways, from asymptomatic patients to severe forms with multisystem inflammatory syndrome in children (MIS-C). Although there are not much clinical data on the SARS-CoV-2 disease in the pediatric population worldwide, we tried to find out whether there is a connection between the severity of this disease, other ARTIs, and vitamin D supplementation. We also aimed to find out if 25OHD deficiency had an adverse effect on the evolution of the disease and the recovery period in the case of younger patients affected by COVID-19. For this literature review, the PICO framework was selected as the methodological approach. Our results demonstrated many methods by which this vitamin may lower the risk of ARTI with regard to the COVID-19 infection. Despite these significant advancements, more research is needed to support the idea that 25(OH)D concentration can influence the evolution of respiratory tract infections in children.<\/jats:p>","DOI":"10.3390\/nu15153430","type":"journal-article","created":{"date-parts":[[2023,8,2]],"date-time":"2023-08-02T10:57:33Z","timestamp":1690973853000},"page":"3430","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Immunomodulatory Effects of Vitamin D in Respiratory Tract Infections and COVID-19 in Children"],"prefix":"10.3390","volume":"15","author":[{"given":"Maria","family":"Nicolae","sequence":"first","affiliation":[{"name":"Department of Pediatrics, County Clinical Emergency Hospital of Constanta, 900591 Constanta, Romania"},{"name":"Department of Pediatrics, Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8844-0593","authenticated-orcid":false,"given":"Cristina Maria","family":"Mihai","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, County Clinical Emergency Hospital of Constanta, 900591 Constanta, Romania"},{"name":"Department of Pediatrics, Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4996-2484","authenticated-orcid":false,"given":"Tatiana","family":"Chisnoiu","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, County Clinical Emergency Hospital of Constanta, 900591 Constanta, Romania"},{"name":"Department of Pediatrics, Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adriana Luminita","family":"Balasa","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, County Clinical Emergency Hospital of Constanta, 900591 Constanta, Romania"},{"name":"Department of Pediatrics, Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Corina Elena","family":"Frecus","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, County Clinical Emergency Hospital of Constanta, 900591 Constanta, Romania"},{"name":"Department of Pediatrics, Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Larisia","family":"Mihai","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, County Clinical Emergency Hospital of Constanta, 900591 Constanta, Romania"},{"name":"Department of Pediatrics, Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2640-8795","authenticated-orcid":false,"given":"Vasile Valeriu","family":"Lupu","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, \u201cGrigore T. Popa\u201d University of Medicine and Pharmacy, 700115 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Irina","family":"Ion","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, County Clinical Emergency Hospital of Constanta, 900591 Constanta, Romania"},{"name":"Department of Pediatrics, Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7234-2814","authenticated-orcid":false,"given":"Alexandru Cosmin","family":"Pantazi","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, County Clinical Emergency Hospital of Constanta, 900591 Constanta, Romania"},{"name":"Department of Pediatrics, Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5872-4381","authenticated-orcid":false,"given":"Andreea","family":"Nelson Twakor","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"Andrusca","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, County Clinical Emergency Hospital of Constanta, 900591 Constanta, Romania"},{"name":"Department of Pediatrics, Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4898-8938","authenticated-orcid":false,"given":"Claudia Simona","family":"Cambrea","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ioan Anton","family":"Arghir","sequence":"additional","affiliation":[{"name":"Department of Pneumophtisiology, Faculty of General Medicine, \u201cOvidius\u201d University, 900470 Constanta, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8147-3632","authenticated-orcid":false,"given":"Ancuta","family":"Lupu","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, \u201cGrigore T. 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