Mackay vet urges horse owners to check Hendra vaccines after confirmed case

Five people are being monitored as close contacts of Queensland’s first Hendra virus case in five years as a vet who identified the symptoms warns of the deadly consequences of not vaccinating horses.

Five people considered close contacts to a horse with the deadly Hendra virus are being monitored as a leading vet urges animals to be vaccinated against the disease.

It comes as an unvaccinated grey Arab cross, considered a pet, was euthanased after it was seen staggering in a paddock in Mackay last week.

It is the first confirmed Hendra case in Queensland in five years.

Northern Beaches Veterinary Hospital owner David Lemmon said he was called to a “very sick horse that was staggering in the paddock” on Thursday morning.

“I assessed the situation and thought it was very neurological and elected to put him to sleep,” he said.

Biosecurity Queensland in Brisbane tested the nasal swabs and blood samples and detected the Hendra virus, and Dr Lemmon was notified on Friday.

“It was definitely an unvaccinated horse,” he said.

“The other horses that were around the place, they were vaccinated so they were completely safe as the vaccine is 100 per cent effective.”

Northern Beaches Veterinary Hospital owner David Lemmon is urging all horse owners to vaccinate their animals against Hendra after he correctly identified the disease in an older Arab cross at a Mackay property. Photo: Lee Constable/File photo

The Mackay Public Health Unit, in a statement, said it was “supporting the response to a confirmed case of Hendra virus”.

“They have identified five people who were in contact with the horse while it was infectious, one of which is considered high risk and the other moderate to high risk,” the statement read.

“These two people will receive a monoclonal antibody infusion.

“No one exposed to the virus has been hospitalised.”

July 2011: There was a Hendra outbreak on a property at Nikenbah. Biosecurity staff moved a horse to a quarantine paddock after testing it for Hendra virus. Picture: Alistair Brightman

The Mackay property is not under quarantine as the horses were vaccinated against the virus.

Biosecurity Queensland on Saturday said it was working to contain an outbreak.

Chief Veterinary Officer Dr Allison Crook said the horse’s condition had rapidly deteriorated.

“Tracing and risk assessments have been undertaken on other animals on the property,” Dr Crook said.

“We are working with the property and horse owners to ensure the risk is contained on the property.”

Racing Queensland said the confirmed case was not a thoroughbred. The racing body said it was committed to keeping the industry protected against the deadly virus.

“Vaccination of horses is the most effective way to help manage Hendra virus disease and a registered vaccine is available to help prevent Hendra virus disease in horses,” a spokesman said.

Dr Lemmon said ensuring horses were up to date with their vaccination was the easiest way to protect both the animal and people.

“I always say to people that if you vaccinate your horse, you’re protecting yourself,” he said.

“There has been four to five cases in Mackay over the years. If you have horses and children, you really should vaccinate because there are flying foxes that fly everywhere.”

The Hendra virus travels through flying foxes. Picture: Craig Warhurst

Horses catch the virus through flying fox faeces either through their water or food, and can show no symptoms for a number of days before developing signs of sickness.

“It is very important to remember that with Hendra virus in a horse, the horse is secreting the virus before it has any clinical signs whatsoever, and that is the scary part about it,” Dr Lemmon said.

“The kids could be kissing or hugging the horse before the horse is secreting the virus.

“People can minimise the risk by not having water troughs under trees – have it away from trees.”

Northern Beaches Veterinary Hospital owner David Lemmon is urging all horse owners to vaccinate their animals. Photo: Lee Constable/File photo

The aged grey Arab cross horse was a pet and had not been taken to any events or horse meets in the weeks before contracting the virus.

Dr Lemmon said there were more than 90 clinical signs of Hendra virus in a horse, and the Mackay animal had no ocular or nasal discharge.

“This horse was entirely neurological … its heart rate, temperature and gut sounds were all normal, but it was staggering and disoriented,” he said, adding that suggested to him early on the horse had a brain infection.

“As far as I was concerned, I euthanased the horse as quick as possible and it was buried right there.”

The Hendra vaccine was developed after the first confirmed case in 1994, and Mackay vet Dr David Lemmon says it has a 100 per cent efficacy rate in protecting animals from the disease. Photo: Claudia Baxter/ File photo

Dr Lemmon hit out at people rubbishing the Hendra vaccine in horses, arguing the efficacy rate outweighed what he said was 0.03 per cent of negative reactions from more than half a million doses.

Horses between the Northern Rivers region and Cairns, particularly along the coast, were at particular risk.

He said vaccinated horses injected with the Hendra virus showed no spikes in heart rate or other clinical signs, suggesting it was 100 per cent effective in preventing the disease and its spread to people.

Dr Lemmon was a close friend to Rockhampton vet Dr Alister Rodgers who died in 2009 after contracting the virus while treating an infected horse at Cawarral.

Dr Rodgers had initially been treating a thoroughbred for a suspected snake bite that later proved to be Hendra.

Dr Lemmon said it was a “very scary experience” for a vet to treat an unvaccinated horse, and warned people to stay away from the animal if they suspected it could be Hendra.

He said the Hendra vaccine course involved two shots about three to six weeks apart, followed by a booster at six months and then a yearly booster.

“It’s very reasonable,” he said.