IL18 and COVID-19: When performing the χ2, we found that the IL-18 TG and GG genotypes were not significantly associated with increased mortality of COVID-19 compared with the IL-18 TT genotypes (p = 0.9, OR = 1.060, 95% CI = 0.413–2.764) and (p = 0.378, OR = 0.449, 95% CI = 0.094–2.063) respectively.