More than 2½ billion people live in dengue endemic areas and about 400 million cases occur each year, making dengue the most rapidly spreading mosquito-borne viral disease. In the last 50 years, the incidence of cases has increased 30 times and cases have moved from rural to urban areas. Dengue kills about 25,000 people each year.
Although dengue is found around the world in subtropical and tropical areas, the World Health Organization (WHO) reports as of March 2020, Asia represents ~70% of the global burden of disease. Cases in the Americas also happen to have the lowest fatality rate. There is a trend of increasing numbers of cases and geographical expansion. Much of this may be due to the expanding environment of the most important vector, the Aedes aegypti mosquito.
Greater than 70% of the world population most at risk for dengue live in Asia and the Pacific region. Epidemic dengue is spreading to more of the Southeast region and new countries have become endemic foci. Case fatality rates of 3-5% have been seen in rural areas of India, Indonesia, and Myanmar, while the worldwide fatality rate averages 1%. In the Pacific island countries, Polynesia had the most cases between 2001 and 2008.
