The Veterinary Nurse Pathway Certificate
Australia Pacifica, Oceania
In Australia’s short history, virus and diseases come in a short list. Within Australia there are thought to be about 780,000 grey-headed flying foxes in more than 100 camps dotted across Australia. While the fruit bats can carry many infectious diseases, one is thought to be the main route of the Hendra virus. Although it is not yet confirmed.
Hendra virus (originally called "Equine morbillivirus") was first discovered in Australia in September 1994. Following an outbreak of illness in horses in a large racing stable in the suburb of Hendra. Where it caused thirteen horses’ deaths and one trainer at the complex.
With the infected horse entering the paddock with all nineteen horses, the other six was substantially euthanized to prevent other infections.
Hendra virus can cause a range of symptoms in horses. Usually there is a rapid onset of illness, fever, increased heart rate and rapid deterioration with respiratory and or neurological symptoms. In humans, symptoms typically develop between 5 and 21 days after contact with an infectious horse. Fever, cough, sore throat, headache and tiredness are common initial symptoms. Meningitis or encephalitis (inflammation of the brain) can develop, causing headache, high fever, and drowsiness, and sometimes convulsions and comas. The Hendra virus infection can be fatal.
The virus can spread from foxes to horses, horses to horses and rarely, from horses to people.
Horses become infected with Hendra after exposure to bodily fluid from an infected flying fox. This often happens in the form of urine, faeces or masticated fruit covered in the flying fox's saliva when horses can graze below roosting sites.
Outbreaks recorded as of June 2014, a total of fifty outbreaks of Hendra virus have occurred in Australia, all involving infection of horses. As a result of these events, eighty-three horses have died or been euthanised. A further four died or were euthanised as a result of possible Hendra infection. The case fatality rate was humans 60% and horses 75%. Four of these outbreaks have spread to humans as a result of direct contact with infected horses. There have been seven human infections since the virus was first detected 17 years ago; four people have died as a result.
Not only does this virus occur in human and horse contact but in 2011 a dog contracted the disease was reported to have HeV antibodies, the first time an animal other than a flying fox, horse, or human has tested positive outside an experimental situation. There is no evidence of transmission to humans directly from bats, and, as such it appears that human infection only occurs via an intermediate host, a horse. Despite this in 2014 the NSW Government approved the destruction of flying fox colonies. The elimination of these colonies, already endangered animals, put these flying foxes in severe risk of extinction.
A vaccine to prevent Hendra virus infection in horses has been available since November 2012. While the vaccine has been shown to be safe and to provide high levels of protection in horses, continued efforts to reduce exposure of horses to Hendra virus are essential.