New compounds may prevent spread of malaria

Researchers at Imperial College London have discovered compounds that can potentially prevent malaria parasites from infecting mosquitoes, which could in turn avoid the spread of the disease to humans.

While malaria can be cured with drugs that kill the replicating form of the parasite, patients still carry dormant forms of the virus that transfer the parasite to a mosquito when it bites the human.

These dormant parasites then mature and multiply inside the mosquito, which can later infect a new person.

The newly identified compounds prevent this maturation of parasite inside a mosquito. After screening more than 70,000 compounds, the researchers identified six with potential to be formulated into drugs.

Imperial College London Life Sciences department professor Jake Baum said: "It took several years to find the right conditions that would stimulate the sexual parasites and to miniaturise the environment, but it was worth it – at our best we were screening 14,000 compounds a week!

"Overall we screened around 70,000 molecules and found only a handful of potent compounds that are both active and safe to use with human cells. It was like finding needles in a haystack."

Baum noted that the combination of a transmission-blocking drug with a standard antimalarial can cure patients, as well as protect the community.

The team has already validated one compound in mice, and are in the process of studying the mechanism of all the compounds and an approach to make them useful as future drugs.

Baum added: "What we propose is antimalarial drugs that protect mosquitoes, blocking the parasites from continuing their infectious journey.

"Since transmission occurs in the mosquito, drugs targeting this process have the added benefit of being naturally much more resistance-proof, which could be essential for eliminating malaria."

As the drugs cannot be given directly to mosquitoes, the researchers will work on stabilising them for administration to humans and to ensure their survival after being transferred into the mosquito.