First isolated in 1994, the virus has since been connected to numerous outbreaks of disease in domestic horses and seven human cases.

[1] Symptoms of Hendra virus infection of humans may be respiratory, including hemorrhage and edema of the lungs, or in some cases viral meningitis.

A seroprevalence of 47% is found in the flying foxes, suggesting an endemic infection of the bat population throughout Australia.

This often happens in the form of urine, feces, or masticated fruit covered in the flying fox's saliva when horses graze below roosting sites.

[21][22] The index case, a mare called Drama Series, brought in from a paddock in Cannon Hill, was housed with 19 other horses after falling ill, and died two days later.

[26] As of June 2014, a total of fifty outbreaks of Hendra virus have occurred in Australia, all involving infection of horses.

On 26 July 2011 a dog living on the Mt Alford property 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.

[31] Timing of outbreaks also appears more likely during the cooler months when it is possible the temperature and humidity are more favourable to the longer term survival of the virus in the environment.

[citation needed] It is not clear why there was a sudden increase in the number of spillover events between June and August 2011.

[32] It is possible flooding in SE Queensland and Northern NSW in December 2010 and January 2011 may have affected the health of the fruit bats.

Biosecurity Queensland's ongoing surveillance usually shows 7% of the animals are shedding live virus.

[114] Following the confirmation of a dog with HeV antibodies, on 27 July 2011, the Queensland and NSW governments will boost research funding into the Hendra virus by $6 million to be spent by 2014–2015.