Breathing in Brisbane’s air, we stand where a medical mystery began. This is Hendra. It is a suburb that unknowingly lent its name to a virus. A virus that sparked fear and research in Australia.
In 1994, Hendra became the epicenter of an outbreak. It caused sickness and death among horses. This led to the discovery of the Hendra virus. The virus was first called Equine morbillivirus. The outbreak tragically claimed the lives of 13 horses. It also infected two humans. One of those humans, Victory Rail, sadly died. He was a prominent racehorse trainer. The training complex at 10 Williams Avenue became ground zero.
The index case was a mare named Drama Series. She arrived from Cannon Hill and fell ill. She was housed with 19 other horses. Two days later, Drama Series died. Soon after, all the other horses got sick. Six surviving horses were euthanized. This was to prevent further transmission of the Hendra virus.
Another outbreak occurred before the Hendra incident. It happened in Mackay, 1,000 kilometers north of Brisbane. Two horses died. Their owner also died after assisting in their necropsies. He first suffered meningitis. He later developed neurological signs. This outbreak was diagnosed later. It was confirmed by the presence of the Hendra virus in the patient’s brain.
Flying foxes are the natural hosts of the Hendra virus. They can carry the virus without showing signs of illness. Horses get infected through contact with flying fox bodily fluids. This often happens through urine, feces or saliva on fruit. Horses graze below roosting sites. A seroprevalence of 47% exists in flying foxes. This suggests the bat population throughout Australia has an endemic infection.
The Hendra virus can cause severe symptoms in both horses and humans. Horses often develop pulmonary edema and neurological signs. Humans may experience respiratory issues. Viral meningitis is also possible. The case fatality rate is high. It is 60% in humans and 75% in horses.
To combat this deadly virus, a vaccine was developed for horses. It became available in November 2012. Vaccinating horses breaks the transmission cycle to humans. A human vaccine would take much longer to develop. By December 2014, 300,000 doses had been given to more than 100,000 horses.
Since the initial outbreak, there have been numerous Hendra virus outbreaks in Australia. All of these involved horses. Four outbreaks have spread to humans. As of June 2014, 50 outbreaks had occurred. Eighty-three horses died or were euthanized.
The emergence of the Hendra virus highlights the importance of understanding zoonotic diseases. Factors like deforestation can increase the risk of spillover. Nutritional stress among bats can also contribute. Protecting our forests and vaccinating horses are crucial. These measures reduce the incidence of Hendra virus.
While standing here in Hendra, it is important to remember the lessons learned. Vigilance, research and proactive measures are essential. They protect both animal and human populations from emerging diseases. The story of Hendra serves as a reminder of the interconnectedness of health and the environment.