There were 45 variables in the LASSO regression and the outcomes displayed that median incubation (onset to shelter) period (≥14 days), fever, distribution of peak temperature (>38°C), sputum production, sore throat, shortness of breath, myalgia or arthralgia, poor appetite, headache, diabetes and CRP (≥10 per L) were predictive factors for patients transforming from mild or moderate type to severe type with nonzero coefficients (Figure 2A, 2B). Here, CRP is linked to diabetes mellitus.