New strategies for prevention and control of vector-borne diseases are emphasizing "Integrated Vector Management" – as an approach that reinforces linkages between health and environment, optimizing benefits to both.
The most deadly vector borne disease, Malaria, kills over 1.2 million people annually, mostly African children under the age of five. Dengue fever, together with associated dengue haemorrhagic fever (DHF), is the world's fastest growing vector borne disease.
Poorly designed irrigation and water systems, inadequate housing, poor waste disposal and water storage, deforestation and loss of biodiversity, all may be contributing factors to the most common vector-borne diseases including malaria, dengue and leishmaniasis.
IVM strategies are designed to achieve the greatest disease control benefit in the most cost-effective manner, while minimizing negative impacts on ecosystems (e.g. depletion of biodiversity) and adverse side-effects on public health from the excessive use of chemicals in vector control.
Rather than relying on a single method of vector control, IVM stresses the importance of first understanding the local vector ecology and local patterns of disease transmission, and then choosing the appropriate vector control tools, from the range of options available.
These include environmental management strategies that can reduce or eliminate vector breeding grounds altogether through improved design or operation of water resources development projects as well as use of biological controls (e.g. bacterial larvicides and larvivorous fish) that target and kill vector larvae without generating the ecological impacts of chemical use.
At the same time, when other measures are ineffective or not cost-effective, IVM makes judicious use of chemical methods of vector control, such as indoor residual sprays, space spraying, and use of chemical larvicides and adulticides; these reduce disease transmission by shortening or interrupting the lifespan of vectors.
IVM provides a framework for improved personal protection/preventive strategies that combine environmental management and chemical tools for new synergies; e.g. insecticide-treated nets (ITNs). Trials using insecticide-treated bednets in some malaria-endemic African countries have shown very substantial reductions in child and infant mortality (1, 2). IVM also supports effective, accessible and affordable disease diagnosis and treatment within the framework of a multi-disease control approach.
IVM requires a multi-sectoral approach to vector-borne disease control. For instance Health Impact Assessments of new infrastructure development, e.g. water resource, irrigation and agriculture, can help identify potential impacts on vector-borne disease upstream of major policy decisions so effective action may be taken.
IVM is not a panacea. However, in many settings, the use of IVM strategies has yielded sustainable reductions in disease and transmission rates. In addition, certain IVM field experiences have been documented as cost-effective in terms of disease control, and potential generators of economic co-benefits in terms of development and growth – although more work needs to be done linking health and economic outcomes.
http://www.who.int/heli/risks/vectors/vector/en/
