CRP and COVID-19: By stratifying patients into high versus low cytokine levels using the cutoffs identified in the severe COVID-19 cases, we found that high IL-19 level in saliva (≥ 850 pg mL−1) of severe COVID-19 cases was predictive of the need for mechanical ventilation and/or death by day 29 following admission, after adjusting for age, male sex, BMI, DM, and COVID-19 severity markers including D-dimer, CRP, and ferritin.