US scientists have reported a major breakthrough in the development of a highly effective vaccine against the deadly Nipah virus, according to a new study published Wednesday in the journal Science Translational Medicine.

This latest advance builds upon earlier work by the scientists, who found that the same vaccine can protect cats from Nipah virus and ferrets and horses from the closely related Hendra virus.

The research group developed a vaccine based on a Hendra virus surface protein, the G glycoprotein, a known target for triggering a protective host immune response. In this study, they used the recently developed African green monkey model of Nipah disease to test three different doses of the vaccine in combination with an adjuvant. All nine vaccinated animals survived a lethal Nipah virus challenge given 42 days after the initial vaccination.

"These findings are really quite promising and appear to offer a real potential treatment for either Nipah or Hendra virus infection in people," said Christopher Broder, professor of microbiology at the Uniformed Services University of the Health Sciences and study corresponding author.

The group is planning additional studies to gather more data to include in an application for possible review by the US Food and Drug Administration to license the vaccine for use in humans. The vaccine is in commercial development in Australia for use in horses.

Both Nipah and Hendra viruses have a high fatality rate in humans -- more than 75 percent for Nipah and 60 percent for Hendra. Infections by these viruses target the lungs and brain, and disease outbreaks have occurred regularly in the past decade. Nipah outbreaks have occurred in Malaysia, Singapore, Bangladesh and India. Hendra outbreaks have remained confined to Australia since its emergence there in horses and humans in 1994. Certain fruit bats, also known as flying foxes, spread the viruses; so far, only Nipah is known to spread from person-to-person.