IL6 and COVID-19: We observed higher levels of bilirubin, D-dimer, C-reactive protein, urea, and plasmatic cytokines, such as IL-1β, IL-6, IL-8, IL-10, IL-17A, IL-23, TNF-α, and IFN-α in individuals with the critical form of acute COVID-19 compared to individuals with the severe and/or moderate WHO clinical forms.