An ability by bats to keep their immune system switched on all the time may provide clues to help protect humans against fatal diseases, say researchers.

A unique immune-system capability in bats, which lets them carry but not be affected by fatal diseases, could provide clues to help protect people, say scientists.

In a discovery believed to be a world-first, the CSIRO-led team found bats keep their immune system switched on all the time, unlike humans who only activate it when we get infected.

This may hold the key to protecting people from deadly diseases like Ebola, said CSIRO's bat immunologist Dr Michelle Baker.

The international research, published in Proceedings of the National Academy of Sciences journals, included experts from CSIRO, Duke-National University of Singapore Graduate Medical School and the Burnet Institute.

"If we can redirect other species' immune responses to behave in a similar manner to that of bats, then the high death rate associated with diseases, such as Ebola, could be a thing of the past," Dr Baker said.

She told AAP that "down the track" scientists could use "some of the leads" to identify what pathways were important to controlling viruses in bats and try to mimic the same response in human cells through a drug.

Bats are a natural host for more than 100 viruses, including Ebola and Hendra virus, but they don't get sick or show signs of disease from them.

"Whenever our body encounters a foreign organism, like bacteria or a virus, a complicated set of immune responses are set in motion, one of which is the defence mechanism known as innate immunity," she said.

"We focused on the innate immunity of bats, in particular the role of interferons - which are integral for innate immune responses in mammals - to understand what's special about how bats respond to invading viruses."

They found bats only have a quarter of the number of interferons found in people and kept their immune systems switched on 24/7.