Researchers are getting close to eliminating mosquitoes carrying the dengue virus after seeing a massive drop in infections in Yogyakarta, Indonesia.
What happened: The infection rate in the city dropped significantly by 77% after scientists released about 6 million mosquitoes infected by the Wolbachia bacteria which is used to target the virus, according to The Guardian.
- “We are really hopeful this will lead to local elimination [of dengue] in Yogyakarta City, and the next stage is to scale up beyond Yogyakarta to other parts of Indonesia,” Director of Impact Assessment at the World Mosquito Program, Dr. Katie Anders, said.
- “By having bacteria there it might prevent the virus from growing, and or [the bacteria] might elicit an immune response in the mosquito that’s protective against the virus,” Anders speculated.
- The infected mosquitoes were released in a 13-square-kilometer (5-square-mile) area in the city.
- Although the mosquitoes were only released in one part of the city, health officials monitored the remaining part using disease control methods.
- In their research, scientists micro-injected the bacteria into the eggs and gradually distributed them into homes over six months.
- Global heating has reportedly contributed to the spread of the dengue virus, Anders said, and urbanization and high population density play a role because the mosquitoes like “to live in urban environments close to people.”
- Professor Adi Utarini from Universitas Gadjah Mada said the study showed “the significant impact the Wolbachia method can have in reducing dengue in urban populations.”
What is Wolbachia virus and how is it effective against dengue: The Wolbachia bacteria can commonly found in 60% of insect species, including mosquitoes, according to the World Mosquito Program.
- The bacteria live inside the insect’s cell and can be passed down from one generation to another through eggs.
- Although they are found in mosquitoes, the bacteria don’t normally infect Aedes aegypti, a breed of mosquito known to be the carrier of several viruses, including dengue, zika and yellow fever.
- Scientists weren’t certain how the bacteria inhibit the transmission of dengue virus into humans, even though it never alters the infected mosquito’s behavior or affects their population.
- Wolbachia is reportedly safe for humans and the environment, according to the organization.
Indonesia was not the first: The organization tested the bacteria in other countries before the trial in Indonesia.
- After a successful initial trial in Australia, the research immediately moved to smaller trials in other parts of the world.
- The organization also applied the same method in parts of northern Queensland where Dengue has been eliminated as a public health concern. The area has no outbreak records for the past five years.