(2) The seroprevalence is the presence of IgG antibodies against DENV, and it is detected using a different diagnostic kit (indirect IgG) to determine recent infection (capture IgM/IgG ELISA); this distinction is relevant because by definition the antibodies detected in the indirect ELISA kit are cross-reactive and only report exposure to DENV in regions where only this flavivirus circulates; in regions where more than one flavivirus circulates, the diagnostic kit reports exposure to flaviviruses16. Here, CD40LG is linked to infection.