The New South Wales, Australia, Department of Primary Industries (DPI) is urging horse owners to remain vigilant, following confirmation of Hendra virus infection in an unvaccinated horse near Lismore.

Christine Middlemiss, BVMS, MRCVS, the NSW Chief Veterinary Officer, said Local Land Services has placed the affected property under movement restrictions.

“This is the first case of Hendra virus confirmed in NSW this year,” Middlemiss said. “Samples from the horse were sent by a private veterinarian for laboratory analysis at DPI’s Elizabeth Macarthur Agricultural Institute (EMAI) and results from testing at EMAI confirmed the Hendra virus last night (July 9).

“The 11-year-old gelding was euthanized near Lismore last night by the Local Land Services district veterinarian,” she added. “The horse was noticed to be lethargic on Thursday, July 6. On Friday, July 7 the horse was not eating and was wobbly on its feet.”

Hendra virus has been known to yield numerous clinical signs in horses including lethargy, respiratory distress, frothy nasal discharge, elevated body temperature (above 40°C, or 104°F), and elevated heart rate; however, authorities caution that hendra infection does not have specific signs.

The virus is transmitted to horses from flying foxes, a type of fruit bat that frequents Australia, but the exact method of transmission remains unclear.

The zoonotic disease is transmissible to humans and has killed four people since it was first discovered, including an equine veterinarian who contracted the virus after treating an affected foal in 2009.

Middlemiss noted this isn’t the first Hendra case confirmed in the Lismore area.

“All known Hendra virus cases have occurred in Queensland or northern NSW, but cases could occur wherever there are flying foxes or in horses that had recent contact with flying foxes prior to movement,” she cautioned.

Australian horse owners should discuss a Hendra virus vaccination strategy with their veterinarians, she recommended.

“Vaccination remains the most effective way of reducing the risk of Hendra virus infection in Horses, but good biosecurity and personal hygiene measures should always be practiced in conjunction with it,” Middlemiss said.

“Horses should also be kept away from flowering and fruiting trees that are attractive to bats,” she added. “Do not place feed and water under trees and cover feed and water containers with a shelter so they cannot be contaminated from above.”

If your horse is unwell, keep people and other animals away from the horse and call your private veterinarian immediately.