In Brazil, the Health Ministry through the Secretary of Health Surveillance establishes the following tests for the laboratory confirmation of cases of COVID-19: molecular biology tests using RT-PCR/RT-LAMP, antigen tests using immunochromatography and the immunological IgM, IgA and/or IgG test using ELISA, immunochromatography (rapid test) for the detection of antibodies, electrochemiluminescence or chemiluminescence immunoassay. Here, CD40LG is linked to COVID-19.