[ad_1]
The fight against malaria could one day rid the mosquitoes themselves of the parasites that cause the disease.
In the laboratory, the antimalarial treatment of female mosquitoes has helped prevent parasites from developing inside insects. The mosquitoes were exposed to treatment when they landed on a glass surface coated with drugs for as little as six minutes, which is comparable to the time mosquitoes spend on protective nets when they hunt for a meal, researchers report online February 27 Nature.
"People have been exploring ways to control pests for a very long time," says Joshua Yukich, a malaria epidemiologist at Tulane University in New Orleans, who did not participate in the research. A strategy that kills mosquito-causing parasites in mosquitoes "is rather exciting." It may be possible to make insecticide-treated mosquito nets even more effective by adding antimalarial compounds, he said.
Malaria, caused by Plasmodium parasites and spread by the bites of Anopheles mosquitoes, is an influenza illness with high fever and chills. Without treatment, this can be fatal: in 2017, there were 219 million cases of malaria worldwide, mainly in Africa, and 435,000 deaths, mostly in children.
Since 2000, an international effort to fight malaria in Africa has prevented about 663 million cases, according to researchers, largely thanks to insecticide-treated mosquito nets. Mosquito nets kill mosquitoes and help protect sleepers from bites. But these advances have been threatened by the appearance of mosquitoes resistant to insecticides.
To determine whether parasite targeting in mosquitoes might work, Flaminia Catteruccia, a molecular entomologist at Harvard T.H. Chan School of Public Health and her colleagues treated a glass surface with atovaquone, an antimalarial drug. The mosquitoes landed on the surface and absorbed the drug through the legs. The compound then went to the gut of insects, where it prevented the parasite Plasmodium falciparum to develop, the team found.
The strategy worked, whether the insects were infected with the parasites before or after the drug treatment. An "autopsy" of the mosquitoes, seven to nine days after a meal of infectious blood, revealed that the insects were free of parasite after treatment with certain doses of the drug, the researchers said.
Atovaquone, used to treat malaria in humans, kills Plasmodium parasites by inhibiting a protein in the mitochondria, energy plants inside the cells. But it is possible to use antimalarial drugs to treat mosquitoes, which could make the parasites more resistant to drugs, thus jeopardizing essential treatments. Catteruccia and his colleagues would like to test other compounds that kill mosquito parasites.
According to Catteruccia, there are already options, including antimalarial drugs that have shown efficacy against parasites in tests but have not been treated, due to absorption problems in the body. human body or other problems. "In a way, we can reuse drugs that are not good enough for human use," she says.
Regarding mosquitoes, the development of resistance should not be a concern, says Catteruccia. In the study, treatment with atovaquone did not shorten the life of insects or affect the reproductive capacity of mosquitoes. "The mosquito does not care to pick up this medicine," she says.
In addition to finding appropriate drugs, it would also be necessary to develop formulations that can remain active on the nets for a few years, Yukich said. Long-lasting insecticide-treated mosquito nets, for example, retain their insect killing power for about three years, even when they are used and washed daily.
[ad_2]
Source link