Dengue is a mosquito-borne viral infection of major global significance. Millions of infections occur annually encompassing a wide clinical spectrum from inapparent infection to severe and potentially fatal disease. The public health and economic burden of symptomatic infections is very high in Viet Nam, especially in the southern provinces. 

Dengue occurs year-round in Vietnam, with peak transmission in the warmer rainy season, April through October in the north and June through December in the south. Elevated risk occurs throughout the Red River Delta and Mekong Delta, and the coastal district and provincial capitals of central Vietnam.