Halting the World's Most Lethal Parasite: Immunizing Mosquitoes and Other 'Crazy' Anti-Malaria Ideas

A new malaria vaccine, a plan to immunize mosquitoes and other "crazy" ideas have brightened prospects for vanquishing this killer

Right now, somewhere in the world—in a petri dish in Baltimore, maybe, or in the salivary glands of a laboratory-bred mosquito in Seattle, or in the bloodstream of a villager in Ghana—resides a chemical compound that could help eradicate human history’s biggest killer. Scientists have many promising malaria vaccine candidates in the works, and for the first time one has reached advanced human trials. If it or another candidate is even partly effective in people, it could save the lives of millions of children and pregnant women. It would be the only vaccine yet developed against a human parasite, an achievement of Nobel caliber. And it could, in its first-generation form, be distributed in Africa as soon as 2015.

“If all goes well, five years from today, a vaccine could start being implemented in a wide way in six- to 12-week-old children,” says Joe Cohen, a scientist who is leading some of the most promising research. “It is a fantastic achievement. We are all very proud of that.” This is an extraordinary moment for malaria vaccine research. So why isn’t Regina Rabinovich singing from the rooftops?

DEADLY CARGO: The Anopheles mosquito carries the malaria parasite responsible for disease and death in much of the tropics.Image: EVA-MARIA PASIEKA Corbis

In Brief

• Vaccines against malaria have encountered repeated failures. New technolo gical approaches have revived the push for an agent that would provide lifelong immunity.
• Late-stage clinical trials will finish this winter on a vaccine that has been under development since the 1980s. It could reduce cases of the most lethal form of malaria by half.
• Even as this work moves forward, researchers are proceeding with other strategies for new vaccines, such as a weakened form of the parasite that is cultured in mosquitoes.
• Because malaria has been so hard to fight in the past, researchers must moderate outsize expectations to keep hopes from being dashed yet another time if new vaccine candidates fail.