Malaria kills hundreds of thousands of people every year. Besides developing drugs to prevent infection, people have been trying to stop the spread of malaria by killing mosquitoes using insecticides.
This approach had been highly effective. But in the past few years increasing numbers of mosquitoes have become resistant to the insecticides.
“In Africa, where malaria is widespread, pretty much every mosquito species that carries the parasite has developed resistance,” says Flaminia Catteruccia at Harvard University. As a result, progress on reducing malaria has plateaued.
Catteruccia and her colleagues wanted to see whether there is another way to stop the transmission of malaria parasites. They found that an antimalarial drug given to travellers visiting areas where the disease is common, called ATQ, also works on mosquitoes.
After keeping 100 mosquitoes in a container with ATQ-treated surfaces for 6 minutes, the team fed these mosquitoes with malaria-infected blood. When they dissected the mosquitoes, the team found no signs of the parasites.
In contrast, over 80 per cent of the mosquitoes that weren’t exposed to ATQ had the parasites. Exposure to ATQ didn’t harm the mosquitoes’ survival rates.
“We are very astonished to see the drug eliminated all parasites,” says Catteruccia. She suggests antimalarial drugs could be added to the coating for mosquito nets, in addition to insecticides.
ATQ wouldn’t be a good candidate for this application, however, because there is a small chance that these parasites can develop resistance to it. This would compromise the effectiveness of ATQ in treating malaria in humans. The team aims to find other drugs that are equally as effective.
Journal reference: Nature, DOI: 10.1038/s41586-019-0973-1