CD40LG and infection: Point‐of‐care lateral flow immunoassay can detect antibodies within 15 min.[11] The sensitivities and specificities of serum IgM and IgG antibodies to diagnose COVID‐19 were 48.1% and 88.9%, and 100% and 90.9%, respectively.[12] The presence of IgG means previous infection, or the patient might be recovered, and the presence of IgM means recent or current infection, while decreasing IgM and increasing IgG during repeated tests indicate that the patient has nearly recovered.[13]