CD40LG and leptospirosis: In the retrospective study, we did not observed any cross-reactivity with Chikungunya virus, Orientia tsutsugamushi or Plasmodium sp.. However when evaluating the SD Bioline Dengue Duo kit, Blacksell et al. [18] reported 12.2% (10/82) of cross-reactivity with Chikungunya virus, 12.5% (1/8) with Orientia tsutsugamuhi and 100% (1/1) with Plasmodium sp. When evaluating only the IgM part of the kit, Hunsperger et al. [19] reported around 35% of IgM cross-reactivity with malaria as well as some false positive results with leptospirosis, tuberculosis and West-Nile infections.