Scientists from the World Mosquito Programme have published new findings from research into the use of Wolbachia to control the spread of dengue via Aedes aegypti mosquitoes.
The research, published recently in the New England Journal of Medicine, found laboratory-reared Aedes mosquitoes infected with a naturally occurring non-harmful bacterium Wolbachia, resulted in a 77 percent decline in dengue cases in trial areas within Yogyakarta city in Indonesia, where the Wolbachia-infected mosquitoes were released.
This approach has been shown to be effective because the males of these infected mosquitoes pass on the Wolbachia to wild females they mate with, and the subsequent generations continue to spread the Wolbachia bacteria, which have the ability to inhibit viral reproduction but with no known environmental impact. The Wolbachia-infected mosquitoes become self-sustaining, causing a rapid reduction in the prevalence of dengue virus.
Why is dengue a problem?
Dengue is a mosquito-borne virus that for several decades has been steadily increasing its spread and impact across the tropical and sub-tropical belts of the world, and will continue to extend its reach, particularly in lower-income settings. The number of dengue cases reported to the World Health Organization (WHO) has grown exponentially over the past two decades; from 506,000 cases in 2000 to over 2.4 million in 2010 and 5.2 million in 2019. The mosquitoes that carry dengue, certain species of the Aedes group, are the same mosquitoes that carry Zika, chikungunya, yellow fever, and others, and these viruses are also on a trend to rising global impact. The speed at which dengue is growing around the world underlines the need for more ongoing research into the disease and its vectors alongside increased investment in solutions that can keep pace with this rapidly growing threat.
Our view on this research
Malaria Consortium’s Senior Vector Control Specialist, Dr Leo Braack, said:
“Malaria Consortium congratulates the research group on the publication of these findings. Similar studies have been replicated in a number of different locations in the world, and represent an entirely new class of tool to combat disease agents. Stringent scientific and environmental trials have shown that this is a safe and socially responsible method.
Whilst encouraging, we will have to wait and see how practical and cost-effective the technique is to scale up.”