Controlling And Preventing Dengue

The only method of controlling and preventing dengue and dengue hemorrhagic fever (DHF) is to combat the vector mosquitoes. In Asia and the Americas, Aedes aegypti breeds primarily in man made containers like earthware jars, metal drums and concrete cisterns used for domestic water storage as well as used automobile tires and other items that collect rainwater, In Africa, it also breeds extensively in natural habitats such as tree holes and leaf axils.

In recent years, Aedes albopictus, a secondary dengue vector in Asia has become established in the United States, several Latin American and Caribbean countries, in parts of Europe and in one African country. The rapid geographic spread of this species has been largely attributed to the international trade in used tires.

The application of appropriate insecticides to larval habitats, particularly those which are considered useful by the householders, prevent mosquito breeding for several weeks but must be reapplied preriodically. Small mosquito eating fish and copepods have also been used with some success. During outbreaks, emergency control measures may also include the application of insecticides as space sprays to kill adult mosquitoes using portable or truck mounted machines or even aircraft.

Regular monitoring of the vectors susceptibility to the most widely used insecticides is necessary to ensure the appropriate choice of chemicals. Active monitoring and surveillance of the natural mosquito population should accompany control efforts in order to determine the impact of the program.