A patient presented to emergency depament with sudden onset of fever, headache, retro orbital pain, and back pain. Dengue was suspected. Which is the most sensitive diagnostic test for dengue?

After an incubation period of 2-7 days, the typical patient experiences the sudden onset of fever, headache, retro orbital pain, and back pain along with the severe myalgia that gave rise to the colloquial designation "break-bone fever." Laboratory findings include leukopenia, thrombocytopenia, and, in many cases, serum aminotransferase elevations. The diagnosis is made by IgM ELISA or paired serology during recovery or by antigen-detection ELISA or -PCR during the acute phase. Ref: Peters C.J. (2012). Chapter 196. Infections Caused by Ahropod- and Rodent-Borne Viruses. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.