Malaria and dengue vector biology and control in Latin America

Abstract

Malaria and dengue are major public-health problems in Latin America. Malaria is transmitted in 21 countries in the region with over 885,000 cases in 2002. Ninety-five percent of the cases occur in the Amazonian countries, mainly in Brazil. The main malaria vectors in Mexico, Central America and Northern South America are Anopheles albimanus and An. pseudopunctipennis, and An. darlingi and An. nuñeztovari in the Amazon and Venezuela. With the exception of An. darlingi, these mosquitoes are zoophagic, present low sporozoite indices and have low survival rates. These characteristics make them poor malaria vectors, supporting only seasonal transmission when mosquito abundance peaks. Over 500 million people live at risk of infection with dengue in the region, and all four dengue virus serotypes are in circulation. Over 482,000 clinical cases and 9,893 dengue hemorrhagic fever (DHF) cases were reported in the region in 2003. Aedes aegypti was introduced in colonial times and extended to most parts of the continent. After eradication from most part of the continent in the late 1950s and 1960s, re-infestation soon occurred. Ae. albopictus was introduced in the region in 1985 and dispersed from the Southern United States into Mexico, Central America and Brazil. The participation of this mosquito in dengue transmission in the area awaits assessment. Several populations with variable vectorial capacities have been identified in Mexico