CD40LG and COVID-19: Suspected COVID‐19 who fulfill any of the following laboratory testing for SARS‐CoV‐2: (i) Positive SARS‐CoV‐2 RT‐PCR testing result; (ii) viral genetic sequence is highly homologous with the known SARS‐CoV‐2; and (iii) positive SARS‐CoV‐2 specific IgM antibody and IgG antibody are considered as confirmed cases.