The deaths, as well as a spike in the number of cases in 2011, resulted in a fast-tracked trial of a preventative measure which could be used for humans who work with horses, in particular horse trainers and vets.
The trial was led by Geoffrey Playford, a disease expert and director of infection management services at Brisbane’s Princess Alexandra Hospital.
Professor Playford said the trial, involving 40 human volunteers, was a great success, with no adverse reactions to the treatment in the test patients.
“This treatment is called a monoclonal antibody, so they’re pre-formed antibodies – it’s not a vaccine – which works against the virus to stop it entering human cells and establishing an infection,” he said.
“We haven’t known before now how safe this antibody treatment was, so it’s been difficult to give advice to an exposed person as to what the potential consequences would be of administering this treatment.”
Professor Playford said the trial’s success meant they were able to recommend the treatment to anyone suspected of being exposed to Hendra virus.
Peter Reid, an equine veterinarian who was involved in the initial outbreak of Hendra in 1994, said the treatment would give vets and others who worked with horses peace of mind.
“Some veterinarians have left practice because of concerns over Hendra, the risk to themselves and their staff,” Dr Reid said.
“The fact that we now have a monoclonal antibody that’s already been used but has now been found to be safe is a big achievement, and the veterinary profession is very grateful for all the work that’s been done.”
The antibody was originally developed in the US, and has been available since 2010, being offered on compassionate grounds to 13 people since then.
More work will be done to confirm the effectiveness of the treatment against different strains of the virus.
Professor Trent Munro, from UQ’s Australian Institute for Bioengineering and Nanotechnology, said there was potential to use the antibody against the lethal Nipah virus, a virus in the same family as Hendra that is found in south-east Asia.
“We are looking at rapid responses to emerging diseases in general … so being ready and having these tools in the toolbox is critical,” he said.
“Whether it’s a vaccine approach or an approach like this where we could potentially have a post-exposure treatment, both things are critical and we’re interested in pushing those forward.”
The trial results were published in the Lancet Infections Disease Journal this week.
Stuart Layt covers health, science and technology for the Brisbane Times. He was formerly the Queensland political reporter for AAP.