In the study conducted in Germany by Moghaddam et al. [127], Se in the serum of 33 ill COVID-19 patients (166 samples analyzed in total) was found to be definitely low (mean ± SD, 50.8 ± 15.7 vs. 84.4 ± 23.4 μg/L of the reference population) to ensure the proper synthesis of selenoproteins, especially SelP (3.0 ± 1.4 vs. 4.3 ± 1.0 mg/L of the reference population). Here, SELENOS is linked to COVID-19.