HLA-DRB1 and influenza: Given its role in SARS-CoV and other viral diseases, such as MERS CoV (HLA-DRB1*11:01 and DQB1*02:02) [20], influenza (HLA-DRB1*0401 and HLA-DRB1*0402) [21], dengue (HLA-DRB1 * 0901 and HLA-A*24) [18], and hepatitis B (HLA- DPB1*09:01, DPB1*04:01, and DQB1*06:01) [22], the HLA system could also be beneficial in treating COVID-19 infections.