SSS 2009-03-17（在线收听）

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

People get malaria from Anopheles mosquitoes that themselves are infected with a protozoan parasite 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’ immunity.

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

Researchers are tinkering with specific mosquito genes to see how they affect the development of the parasite. Their goal is to develop a genetically modified mosquito with a strengthened immune system that kills all the parasites. They say next they’d need to get the gene 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.