A horse vaccine against the Hendra virus is to be rolled out in Australia this month, starting in Queensland and northern New South Wales.
The vaccine is for the first time now commercially available, in a major breakthrough in the fight against the bat-borne virus, which jumps from horses to humans.
Horses are believed to contract the virus from feed contaminated by flying foxes' urine, saliva or birthing fluids.
There's no known cure for Hendra, but the Equivac HeV vaccine breaks the cycle of transmission and will prevent human deaths, scientists say.
The project leader is the CSIRO's veterinary pathologist Deborah Middleton, who says the vaccine is the result of extensive research conducted over the past 18 years since the virus was first detected.
"For the first time, we have a specific control measure against a terrible virus which can make a healthy horse or healthy human mortality ill within 48 hours," Dr Middleton told AAP.
"Because so far all human infections have resulted from sick or dead horses, this will break that cycle of transmission."
Dr Middleton said that while Hendra was not easily transmitted, its mortality rate of 75% in horses and 70% in humans, ranking it with the ebola virus as the world's most severe biosecurity threats.
Four out of seven infected people have died from the virus, all in Queensland, since it was identified in 1994.
Batches of the vaccine are to be rolled out from Thursday, a year earlier than expected after a boost from commonwealth and state funding.
Priority will be given to Queensland and northern New South Wales, considered high-risk areas because of previous Hendra outbreaks.
Horses will be given a shot followed by a booster within three weeks.
Australia's largest animal health company, Pfizer Animal Health, will oversee the training and accreditation of vets working with the vaccine.
Vets will be required to record details of horses vaccinated for a national register to be managed and distributed by Pfizer.
The Australian Veterinary Association is still recommending that water and feed troughs be moved away from flying-fox roosts and that protective gear be worn, including overalls, goggles and masks, when handling sick horses.
The virus was discovered after an outbreak of a mystery illness in a large racing stable in the Brisbane suburb of Hendra in 1994. It resulted in the death of horse trainer Vic Rail and of dozens of horses.
