Hendra virus: A virus, formerly called equine morbillivirus, that can cause illness in horses and humans. First identified in 1994 in Australia where the virus caused the death of two patients, one of pneumonia and the other of encephalitis that developed a year after the patient's initial exposure.
Hendra virus is widely distributed in fruit bats (Megachiroptera) in Australia, suggesting that fruit bats may be the natural host of the virus. Hendra virus-infected fruit bats have also been reported in Papua New Guinea.
Hendra virus is a Paramyxovirus similar but not identical to Nipah virus, another agent of zoonotic viral disease, in which bats are thought to be the host.