News & Information - The Mercury - July 2009 Mercury

by Tiffany Holloway
MRMC

Normally, when a person has a blood sucking mosquito embedded in their arm, they think nothing of it. The result is a bump. However, in areas like sub-Saharan Africa, South East Asia, Central and South America and India, mosquito bites can turn deadly if they are infected with Plasmodium parasites, the pathogen responsible for malaria.

This severe and incapacitating disease is a global problem which is estimated to lead to 350-500 million episodes of malaria and anywhere from 1 to 3 million deaths worldwide, mostly children. Today, at least half of the world's population, or 3.3 billion people, are at risk of malaria.

Unfortunately, there is no licensed or approved malaria vaccine available. Antimalarial drugs have either already failed in parts of the world or are threatened with the specter of rapidly developing resistance.

The good news is the Walter Reed Army Institute of Research and the Naval Medical Research Center are on the cutting edge of a vaccine to prevent infection.

"WRAIR and GlaxoSmithKline have co-developed the malaria vaccine, RTS,S. The vaccine is the result of a 23-year collaboration between WRAIR and GlaxoSmithKline. RTS,S is the most advanced malaria vaccine in development in the world. This vaccine has demonstrated about 50 percent effectiveness in volunteers who were exposed to malaria parasites by being bitten by mosquitoes. Although the level of protection is below that required for military use, the vaccine has tremendous potential to save millions of lives in infants and children throughout the world," said Ockenhouse. "This is one example on how the medical research at WRAIR has benefited the world."

This vaccine is now in the last stage of clinical testing in thousands of infants and small children throughout Africa before eventual licensure.

Not only has WRAIR helped develop RTS,S, but the institute also developed Intravenous Artesunate, a drug for severe malaria. The disease can be so severe that the person can no longer take oral medications and an intravenous drug is all that can be used to save a person's life.

Medical Research and Materiel Command donated 1,000 vials to the Centers for Disease Control and assisted in getting a Compassionate Use Protocol through the FDA. Over the first year of use under this protocol, almost 50 lives were saved by this drug, including U.S. military personnel.

Compassionate Use means the drug is still under investigation and will be used under very strict guidelines because it is considered life-saving and there are no other good options available to save the life of a person afflicted with a disease for which the drug may provide treatment.

MRMC also donated 500 vials of the drug in February to the Canadian Malaria Network operating out of the Ottawa Hospital. Here the drug will be made available on Compassionate Use just like through the CDC in the U.S.

"Malaria today still kills, not as much in the U.S. as in other parts of the world, but we still have people die from severe malaria in the US every year. In the last few years alone, there are over 1,500 cases of malaria in the U.S. every year. Overseas the toll is more striking. In Africa, it is estimated that 3,000 kids (enough to fill six 747 planes) die every day from malaria," said COL Peter Weina, chief of pharmacology at WRAIR’s division of experimental therapeutics.

From the July 2009 Mercury, an Army Medical Department publication.