CD4 and COVID-19: After adjusting for age, gender, comorbidities and severity at admission, the multivariate logistic regression analysis demonstrated that low levels of CD3+ cell (< 565.50 cells/μl), CD4+ cell (< 203.50 cells/μl), and NK cell (< 147.50 cells/μl) were significantly associated with disease progression in COVID-19 patients treated with azvudine (OR = 4.198, 95% CI = 1.155–15.262, p = 0.029; OR = 4.313, 95% CI = 1.645–11.307, p = 0.003; OR = 3.345, 95% CI = 1.436–7.791, p = 0.005; respectively) (Table 4).