Hendra virus (HeV) occurs naturally in flying foxes where it appears to cause little or no signs of illness. For reasons not yet completely understood, at times the virus is shed by flying foxes in their body secretions including urine, faeces, saliva and birthing fluids. Horses can become infected by HeV if they ingest or inhale these contaminated body secretions and subsequently develop a serious disease. The virus can, in turn, be transmitted to humans and cause a potentially fatal illness. To date four out of seven people who became infected with the virus have died.
Clinical signs in sick horses are variable but they will often develop a fever and appear unwell. There is usually respiratory distress with nasal discharge and sometimes neurological signs such as twitching, circling and unsteadiness. Although flying fox secretions are the most common means of horse infection, horse-to-horse infection also appears to occur.
Humans become infected from handling infected horses without using protective clothing and equipment. There is no evidence that humans can become infected through direct contact with infected flying foxes. However, precautions should still be taken when handling flying foxes.
The first case of a dog testing positive to HeV antibodies occurred on a property with infected horses. It is thought that the dog became infected from the horses. There is currently no evidence that dogs can transmit the disease to humans.
A vaccine has been developed to protect horses from Hendra disease. The RSPCA strongly supports the vaccination of all horses in areas at risk of Hendra disease. To date, the disease has been found on properties from far north Queensland to the mid-north coastal region of New South Wales. Areas where flying foxes are active are considered high risk.
All persons interacting with horses should take steps to protect themselves from the potential risk of coming into contact with the Hendra virus.
For the latest information on Hendra virus, the vaccine and advice on these protective steps please visit:
- Biosecurity Queensland: https://www.business.qld.gov.au/industries/farms-fishing-forestry/agriculture/livestock/animal-welfare/pests-diseases-disorders/hendra-virus
- New South Wales Department of Primary Industry: http://www.dpi.nsw.gov.au/animals-and-livestock/horses/health-and-disease/hendra-virus/faqs