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full screen Employees of the Doctors Without Borders project began releasing over eight million mosquitoes in Tegucigalpa last year. Archive image. Photo: Elmer Martinez/AP/TT
Dengue-spreading mosquitoes in Honduras have found a new enemy – other mosquitoes.
The method has been tested in the past year with promising results.
– They are difficult to eradicate in other ways, says mosquito researcher Tobias Lilja at SVA.
The number of cases of dengue fever has increased explosively in the world. The viral disease usually has only mild symptoms, but can become serious and, according to some estimates, is behind up to 40,000 deaths a year.
According to the organization Doctors Without Borders, more than half of the world’s population already lives in areas where dengue fever is present. Another billion people are estimated to be in the risk zone in the future due to climate change.
But there is a small lightening. A method tested by Doctors Without Borders in Honduras seems to work.
Promising results
In the project, more than eight million mosquitoes carrying the bacterium Wolbachia – which has been shown to be able to prevent the mosquitoes from spreading, for example, dengue, zika and chikungunya – have been released in the El Manchén district of the capital Tegucigalpa.
Seven months after the last mosquitoes were released, the bacteria was present in 85.7 percent of mosquitoes in the area, according to preliminary results from the project.
At the same time, the number of dengue cases in El Manchén has decreased significantly.
Swedish case?
The method has previously been tested in other locations as well.
– When you release infected mosquitoes, you hope that they will take over the population, says Tobias Lilja, mosquito researcher at the Norwegian Veterinary Institute (SVA).
– The idea is to get a mosquito population in the area that can no longer transmit the virus.
The risk of mosquitoes spreading dengue fever in Sweden is considered to be relatively small. However, Swedish researchers expect that we will have cases of Nile fever, via the so-called West Nile virus.
– Dengue probably requires slightly higher temperatures for there to be enough virus in the mosquitoes for it to spread further. But definitely Nile fever, says Tobias Lilja.