The Eliminate Dengue Program is developing an approach to fighting mosquito-transmitted diseases by using naturally occurring bacteria that reduce the ability of mosquitoes to transmit harmful human viruses such as dengue fever.
The bacterium, called Wolbachia, is a natural bacterium that is present in several different insect species and is safe for humans, animals and the environment. However, when the bacterium is introduced to the Aedes aegypti mosquito, it stops viruses from growing inside the mosquito and from transmitting to people. Mosquitoes cause millions of deaths every year. The Aedes aegypti mosquito is responsible for the spread of several diseases such as dengue fever, chikungunya, yellow fever and Zika.
Since 2011, the Eliminate Dengue Program has been conducting trials in dengue-affected areas such as Australia, Vietnam, Indonesia, Brazil, Columbia and India. The trails include the release of Wolbachia-infected mosquitoes that breed with wild mosquitoes, establishing the bacteria in the wild mosquito population. Wolbachia can sustain itself in mosquito populations, making this method sustainable and cost-effective in the long-term. The program is targeted to cost U.S. $1 per person. This distinguishes the program from other similar initiatives like the Oxitec program.
Oxitec developed genetically modified male mosquitoes that have a gene preventing offspring from surviving to maturity. The aim is to reduce the mosquito population. This is a more expensive approach because a huge number of mosquitoes have to be released continuously.
In 2016, the Eliminate Dengue Program received additional funding to roll out the program in large areas of Brazil and Colombia to stop the spread of the Zika outbreak. The program is funded by the Wellcome Trust, the Bill and Melinda Gates Foundation, and the Brazilian, U.K. and U.S. governments. The World Health Organization also called for large-scale pilot studies of the Wolbachia mosquito-control method to establish its effectiveness in fighting mosquito-transmitted diseases in humans.
The possibility exists that this approach might provide a similar result in the Anopheles mosquitoes that spread malaria.
– Helena Kamper
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