CD40LG and dengue disease: Here in our study, all the chikungunya real-time RT-PCR positive samples were negative for dengue NS1 antigen and anti-dengue IgM antibody by ELISA, as well as dengue-specific nucleic acid by real-time RT-PCR as most of the chikungunya affected areas overlap with dengue endemic regions, and this can cause the mosquito vector to carry both the agents.