What is HENDRA VIRUS (HeV)?
First identified in 1994, this previously unknown virus has been classified as a new genus within the Paramyxoviridae family. It is more commonly known as Hendra, the name of the Brisbane suburb in which the first outbreak occurred.
To date, seven people, all in the State of Queensland, have contracted Hendra Virus in the past 15 years. There is no known treatment, and four of the victims have died following an influenza-like illness which can progress to pneumonia or encephalitis type symptoms (brain inflammation).
All victims contracted Hendra directly from horses. There is no evidence of human to human transmission.
How is it spread?
Despite extensive research into flying-foxes and other mammals, the route of transmission to horses is still not known. The only proven route of transmission is from horses to humans.
The virus itself and every type of bodily fluid (including urine, saliva and faeces) from deliberately infected flying-foxes has been tested on horses, but scientific research was unable to successfully transfer the virus. The experiments did however transfer the virus to guinea pigs and a cat.
Flying-foxes are known to have antibodies to Hendra virus, yet the virus has not been isolated from any free living flying-fox in Australia.
The findings so far suggest that flying-foxes are a natural host of Hendra virus, but spillover of the virus to horses seems to be a rare event. It is believed that the loss of habitat and natural food sources has increased the stress on the flying-fox population which in turn can trigger the manifestation of the virus.
Previously, horses infected with Hendra presented with a blood-stained mucous nasal discharge, but in later cases symptoms similar to neurological disorders and snake bite were reported. Exposure to any bodily fluids and possibly inhaling airborne mucous from sick and infected horses can transfer the virus to humans.
What can you do?
Until the true cause of the Hendra virus and its route of transmission to horses has been established, those who own or work with horses should take steps to reduce risk factors to protect themselves and the animals. Sensible precautions include avoiding contamination by ensuring feed and water dishes are away from trees where bats are known to gather, maintaining good hygiene and remaining vigilant for any symptoms that suddenly appear in a previously healthy horse.
IT IS IMPORTANT TO EMPHASISE THAT HUMANS DO NOT GET HENDRA VIRUS DIRECTLY FROM FLYING-FOXES
For further information: CSIRO