[Dengue in the Americas].

Dengue fever is endemic from Argentina to Mexico, where serotypes 1, 2 and 4 are in wide circulation. After an absence of almost 20 years, serotype 3 arrived in Central America in late 1994. Over the past decade dengue has become a major public health problem in many of these countries, with an increase in the prevalence of dengue haemorrhagic fever and in the number of fatal cases. The situation is not new; there is evidence of a least eight pandemics from the early 19th century until the initiation of the Aedes aegypti eradication campaign in 1947. The resurgence of serious disease was predicted in the early 1980's, and has followed a pattern of increasing severity observed 20 years earlier in Asia.