As already reported by previous studies including samples from patients infected with different viral, bacterial and parasitic pathogens [26,28,29,40,41], specificity was found to be high (> 97%) for both the SD Bioline Dengue Duo NS1 and the SD Bioline Dengue Duo IgM test when testing samples from Laotian patients suffering from other febrile diseases including malaria, chikungunya, scrub typhus and spotted fever. The gene discussed is CD40LG; the disease is spotted fever.