A case was considered laboratory-confirmed dengue when acute DENV infection was demonstrated by: detection of DENV RNA by RT-PCR; isolation of DENV; seroconversion of DENVspecific IgM antibodies observed by MAC-ELISA in paired acuteand convalescent-phase samples; and/or a $4-fold increase in anti-DENV antibody titer measured using Inhibition ELISA [22] [23] [24] [25] in paired acute and convalescent samples. DENV serotypes were identified by RT-PCR and/or virus isolation.