Background: Acute febrile illness (AFI)is specified as sudden onset of fever of unknown origin lasting for 1-14 days. AFI may be caused by pathogens like bacteria, viruses, parasites, and fungi leading to infectious diseases. Dengue is a vector-borne viral disease that is transmitted by Aedes aegypti mosquitoes. Dengue NS1 Ag is released into the blood during viral replication in infected patients and is detectable from the first day after fever. As NS1 Ag can be identified promptly, it acts as a beneficial biomarker for the early detection of dengue, allowing rapid management of dengue fever