CD40LG and infection: Three types of seroconversion are possible: synchronous seroconversion of IgG and IgM, IgM seroconversion earlier than that of IgG and IgM seroconversion later than that of IgG (Long et al., 2020); specific data on the production of IgG and IgM is crucial to allow the rapid identification of the infection (di Mauro Gabriella et al., 2020).