Two new vaccines may eventually protect humans from the Ebola and Marburg viruses plaguing Africa.

Researchers found that a single injection of an experimental vaccine effectively protected monkeys from the Ebola virus. A similar vaccine developed by the same researchers also protected monkeys against the Marburg virus.

They say it's the first time a Marburg vaccine has been shown to work in monkeys.

There is no known cure or treatment for the Ebola or Marburg viruses in humans. But researchers say the results of their study show that vaccines may have the potential to protect humans from these deadly viruses.

Vaccine May Ease Ebola Fears

The Ebola and Marburg viruses cause extreme fever that leads to internal bleeding and usually result in death in both humans and nonhuman primates. A large number of deaths in Africa, particularly in Angola, has been attributed to the rapid spread of these viruses and has led to fears that the viruses may be used as bioterrorism agents.

In the study, published in the July issue of Nature Medicine, researchers describe two new vaccines developed to combat the viruses.

The vaccines contain an inactivated strain of the Ebola or Marburg virus, which causes the body to mount an immune response to combat the virus without the virus causing illness.

In experiments with monkeys, researchers found one dose of the Ebola vaccine prevented the illness in primates. The same effect was seen with the Marburg vaccine.

Further research will be needed before the vaccines may be approved for use in humans.

By Jennifer Warner, reviewed by Michael W. Smith, MD

SOURCES: Jones, S. Nature Medicine. July 2005. News release, Nature Journals.