Effects of vitamin D and zinc deficiency in acute and long COVID syndrome.

Objectives: Acute inflammatory or neuropsychiatric symptoms, such as headache, fatigue, anosmia, and hyposmia, sometimes persist for more than 30 days or longer than 12 weeks after infection with the Omicron variant of SARS‑CoV‑2 (hereafter referred to as COVID-19). The aim of this study was to determine whether detection of zinc concentration or vitamin D concentration could provide treatment benefits for patients with COVID-19, thus reducing the risk of them experiencing long COVID.

Methods: The interval between the date of COVID-19 diagnosis and the date of visit to pulmonary department for prolonged symptoms of COVID-19 was recorded for statistical analysis. Inductively coupled plasma mass spectrometry for detecting zinc and chemiluminescence immunoassay for detecting vitamin D were performed in laboratory tests.

Results: Fifty-five patients were included. Of the participants, 29.1 % and 27.3 % had vitamin D and zinc deficiency, respectively. On average, the patients underwent long COVID treatment for 31.7 ± 17.7 days. A positive statistical correlation was observed between vitamin D and zinc concentrations (Pearson's correlation = 0.378). Compared with sufficient zinc levels, zinc deficiency was associated with a higher fibrinogen level (p < 0.05). Within 30 days, the observed vitamin D deficiency rate was only 21.4 %; after 30 days, the vitamin D deficiency rate rose to 37.0 % (McNemar's chi-square test; p < 0.05).

Conclusion: Zinc deficiency correlates to acute and persistent inflammation and vitamin D deficiency is associated with delayed recovery in long COVID syndrome.