CRP and susceptibility to pneumonia measurement: Regarding laboratory data, we found a significantly higher proportion of lymphocytes among white blood cells and a substantially lower CRP level in cases with SARS-CoV-2-associated pneumonia that was robust for age and sex adjustment (mean difference [MD]: 3.3, 95% CI: 0.1–6.6%, − 53, 95% CI: 16–90 mg/l, respectively) (Table 1).