Dengue fever and dengue hemorrhagic fever (DHF) are acute viral infections commonly found in tropical regions, caused by four closely related serotypes of the Dengue virus, which belongs to the Flavivirus genus in the Flaviviridae family. This test detects the presence of the NS1 antigen in the serum, an early biomarker of Dengue infection. The NS1 antigen is detectable from the first day of fever onset and helps in the early diagnosis of Dengue fever.