This is scientific American's 60 second science. I'm Christopher Intalyata. Got a minute?

When a virus invades your cells, it kicks your immune machinery into motion.

And the first responders are signaling proteins called interferons.

And they trigger downstream immune responses. So you can kind of think of them as

kind of the hormones of the immune system. They're triggered and then

they stimulate a bunch of other immune responses that are more specific to

that pathogen. Michelle Baker, a comparative immunologist at the Australian

Animal Health Laboratory.

In the spirit of comparative immunology, Baker and her colleagues looked at how another mammal,

the black flying fox, a type of bat, handles infections.

They sequenced its immunity genes

and observed the immune response in normal bat cells.

And they found that, unlike us,

the bats always have interferons on patrol,

meaning the proteins don't wait to be activated by invaders.

And the researchers say that this constant state of high alert may be why bats can carry

Ebola, NEPA virus, and a whole host of other infections, with no symptoms at all.

The findings appear in the proceedings of the National Academy of Sciences.

So why not switch on those interferons 24-7 in humans?

Well, in us they tend to cause lots of inflammation and cell damage.

Like the symptoms you feel from the flu,

a lot of that's your immune system's fault, but the key might be to do as the bats do.

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