Health

#28: Hepatitis B
 Boosts Malaria Vaccine

Fragments of hepatitis B, which put the immune system on high alert, make a new malaria vaccine the most successful yet.

By Elizabeth SvobodaJan 5, 2012 12:00 AM

Newsletter

Sign up for our email newsletter for the latest science news
 

A vaccine conferring immunity to only half the people receiving it is not generally considered a success, but malaria is a special case. The mosquito-borne disease caused by the Plasmodium parasite kills more than 700,000 people every year, the vast majority of them African children, and no vaccine has ever shown efficacy in trials. So in October, when drug maker GlaxoSmithKline announced that its new malaria vaccine cut African youngsters’ infection rates by about half in a large trial, global health officials rejoiced.

For years, scientists failed at developing malaria vaccines because Plasmodium changes its structure to trick the immune system. So the researchers behind the new vaccine—called RTS,S—did not formulate the vaccine just to fend off the parasite. Instead, the vaccine is designed to enhance natural immunity so the body flushes out the parasite before it gets entrenched. The vaccine contains hepatitis B antigens and protein fragments of Plasmodium falciparum, the species that causes most malarial infections. “We know the body develops a very strong immune response against hepatitis B,” says Mary Hamel, a medical epidemiologist at the Centers for Disease Control and Prevention and a principal investigator for the African trial [PDF]. “The vaccine fools the immune system into generalizing the response against malaria.”

This strategy does not always prevent infection, which explains the 50 percent failure rate. (The polio vaccine, by contrast, is more than 80 percent effective.) Even so, Hamel says RTS,S could save hundreds of thousands of lives. The trial runs until 2014, so continued success could enable children to receive immunizations by early 2015.

1 free article left
Want More? Get unlimited access for as low as $1.99/month

Already a subscriber?

Register or Log In

1 free articleSubscribe
Magazine Examples
Want more?

Keep reading for as low as $1.99!

Subscribe

Already a subscriber?

Register or Log In

More From Discover
Recommendations From Our Store
Shop Now
Stay Curious
Join
Our List

Sign up for our weekly science updates.

 
Subscribe
To The Magazine

Save up to 70% off the cover price when you subscribe to Discover magazine.

Copyright © 2021 Kalmbach Media Co.