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This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute.

People get malaria¹ from Anopheles mosquitoes that themselves are infected with a protozoan parasite² called Plasmodium. The mosquitoes do have immune systems. But the parasite has figured out how to get past the mosquito’s defenses. So researchers at Johns Hopkins University Malaria Research Institute are trying to help people—by pumping up the mosquitoes’ immunity³.

When a mosquito takes some blood from a human, she may also ingest Plasmodium. The parasite ends up in the insect’s gut⁴. The mosquito immune system jumps into action as the parasites⁵ try to push through the gut wall. Most parasites do get killed, but some manage to survive that gut migration⁶. Then they replicate⁷ and move to the salivary⁸ glands⁹, ready to infect the next person the mosquito bites.

Researchers are tinkering with specific mosquito genes¹¹ to see how they affect the development of the parasite. Their goal is to develop a genetically¹² modified mosquito with a strengthened immune system that kills all the parasites. They say next they’d need to get the gene¹⁰ into enough wild mosquitoes that they would breed and pass that gene on. No simple effort. But if it works, it could be a big victory in the war against malaria.

Thanks for the minute for Scientific American's 60-Second Science. I'm Cynthia Graber.