This test is done to assess the quantitative detection of antibody titer of Dengue Virus as an aid to the diagnosis of Acute Dengue infection. significant change in titer are useful to confirm clinical diagnosis of infection.Determination of dengue infection by the detection of antigen and antibody to NS1. NS1 is a structural protein which is secreted by all flaviviruses, and is detectable up to 10 days after onset of illness. The NS1 antigen will disappear once seroconversion has occurred in the host. Both antigen-capture ELISAs and lateral flow-antigen detection methods are used, as well as NS1-specific IgM and IgG assays.