IL6 and Fever: Fever symptoms (HR=0.57; 95% CI 0.36-0.90) and elevated IL-6 levels (> 2.9 pg/ml) on admission (HR=0.50; 95% CI 0.30-0.86) were unfavorable factors for discharge (all HRs <1 and all P-values <0.05) (Figure 3, C).