biostudies-literatureWang JGSelf-Funded Scientific Research Project of Guangxi Zhuang Autonomous Region Health Commissione40245https://www.ebi.ac.uk/biostudies/studies/S-EPMC11537629biostudies-literatureUnknown103(44)<h4>Background</h4>To explore the relationship between vitamin D levels and risk of SARS-CoV-2 infection and its severity in children and adolescents, and provide a theoretical basis for clinical practice.<h4>Methods</h4>The PubMed, Web of Science, Embase, MEDLINE, and Cochrane Library databases were searched for comprehensive cohort and case-control studies on the association between childhood vitamin D deficiency and the risk and prognosis of coronavirus disease-2019 (COVID-19). The search period was set from December 1, 2019, to December 31, 2023.<h4>Results</h4>The vitamin D insufficiency rate in children with COVID-19 was 80.78% (95% CI, 62.6% to 93.89%), with a deficiency rate of 32% (95% CI: 19.01% to 46.61%). Vitamin D insufficiency was more common in children with COVID-19 than inMedicineVitamin D levels in children and adolescents are associated with coronavirus disease-2019 outcomes: A systematic review and meta-analysis.PMC11537629Z20210123Liang QYWang JGDou HHfalseVitamin D levels in children and adolescents are associated with coronavirus disease-2019 outcomes: A systematic review and meta-analysis.<h4>Background</h4>To explore the relationship between vitamin D levels and risk of SARS-CoV-2 infection and its severity in children and adolescents, and provide a theoretical basis for clinical practice.<h4>Methods</h4>The PubMed, Web of Science, Embase, MEDLINE, and Cochrane Library databases were searched for comprehensive cohort and case-control studies on the association between childhood vitamin D deficiency and the risk and prognosis of coronavirus disease-2019 (COVID-19). The search period was set from December 1, 2019, to December 31, 2023.<h4>Results</h4>The vitamin D insufficiency rate in children with COVID-19 was 80.78% (95% CI, 62.6% to 93.89%), with a deficiency rate of 32% (95% CI: 19.01% to 46.61%). Vitamin D insufficiency was more common in children with COVID-19 than in2024-01-01T00:00:00Z2024 Nov2025-04-04T03:06:08.781Z2025-04-04T03:06:08.781ZS-EPMC115376293949597510.1097/MD.0000000000040245