Zinc and selenium status in coronavirus disease 2019

We systematically analyzed and attempted to discuss the possibility that deficiencies of zinc or selenium were associated with the incidence and severity of COVID-19. We searched for published and unpublished articles in PubMed, Embase, Web of Science and Cochrane up to 9 February 2023. And we selected healthy individuals, mild/severe, and even deceased COVID-19 patients to analyze their serum data. Data related to 2319 patients from 20 studies were analyzed. In the mild/severe group, zinc deficiency was associated with the degree of severe disease (SMD = 0.50, 95% CI 0.32-0.68, I² = 50.5%) and we got an Egger's test of p = 0.784; but selenium deficiency was not associated with the degree of severe disease (SMD = - 0.03, 95% CI - 0.98-0.93, I² = 96.7%). In the surviving/death group, zinc deficiency was not associated with mortality of COVID-19 (SMD = 1.66, 95%CI - 1.42-4.47), nor was selenium (SMD = - 0.16, 95%CI - 1.33-1.01). In the risk group, zinc deficiency was positively associated with the prevalence of COVID-19 (SMD = 1.21, 95% CI 0.96-1.46, I² = 54.3%) and selenium deficiency was also positively associated with the prevalence of it (SMD = 1.16, 95% CI 0.71-1.61, I² = 58.3%). Currently, serum zinc and selenium deficiencies increase the incidence of COVID-19 and zinc deficiency exacerbates the disease; however, neither zinc nor selenium was associated with mortality in patients with COVID-19. Nevertheless, our conclusions may change when new clinical studies are published.