Brazilian researchers have released mosquitoes infected with dengue-blocking bacteria as part of the ‘Eliminate the dengue: Challenge Brazil’ project to fight against fever through a natural means.
Around 10,000 mosquitoes infected with bacteria that suppress dengue fever have been released by state Brazilian laboratory Fiocruz to let them multiply and breed, becoming a majority and reducing cases of the disease.
Mosquitoes are infused with intercellular bacteria Wolbachia, which is found in 60% of insects that will not transmit to humans.
A similar number will be released each month for four months, with the first release in Tubiacanga, in the north of Rio.
Fiocruz is implementing the project in Brazil, which is also taking place in Australia, Vietnam and Indonesia. The programme began in 2012.
Wolbachia acts similar to a vaccine for the mosquito Aedes aegypti that transmits dengue, and prevents the dengue virus from multiplying in its body by suppressing reproduction. If a contaminated male fertilises the eggs of a female without the bacteria, these eggs do not turn into larvae. But if the male and female are contaminated or if only a female has the bacteria, all future generations of mosquito will carry Wolbachia.
The research on Wolbachia commenced at the University of Monash in Australia in 2008. During the period 2009-2014, Brazil reported around 3.2 million dengue cases, which resulted in approximately 800 deaths.