A horse in Queensland has contracted the rare bat-borne lyssavirus, the first time ever for an animal in Australia.

Biosecurity Queensland says the horse was euthanased on May 11 after falling ill.

The property, in the Southern Downs region in southeast Queensland, has been quarantined.

Chief biosecurity officer Jim Thompson said another horse had shown similar symptoms on the same property and was also put down.

There are 20 other horses on the quarantined property.

The lyssavirus, which is similar to rabies, was thought only to affect bats and humans.

Lyssavirus invariably leads to death in mammals through fatal encephalitis, or swelling of the brain.

In February an eight-year-old boy died from the rare virus in Brisbane. He had been scratched by a bat in Cairns in far north Queensland in December before falling ill.