Plasmodium falciparum, the parasite that causes malaria.: Photo courtesy NIH
Malaria is one of the most deadly diseases in the world. Spread by mosquitoes, each year it kills more than 1 million people, and makes 300 million seriously ill, mostly children, mostly in Africa.

For years researchers have tried to find a vaccine that will prevent people from contracting the disease. The problem is, the parasite enters the bloodstream at a particular phase in its life cycle. Collecting the parasite at that stage is tricky, because it lives in the salivary glands of the mosquito.

But now a research lab in suburban Maryland has figured out a way to collect the parasites. They breed their own highly infectious mosquitoes, which they keep locked behind five doors so none escape. Once the parasite has reached the proper stage, workers kill the mosquitoes and extract the parasite.

After they collect the parasite, they disable it and render it harmless. It can then be injected into a person. The body recognizes the parasite as a foreign body and produces antibodies to fight it. These antibodies stay in the bloodstream, protecting the person from any real parasites they may later pick up.

Early test indicate the vaccine could be up to 90% effective, and protect against malaria for 10 months or more. Human trials are to begin next year.

You can learn more about malaria in The Science Museum’s on-line exhibit.