Rabies is caused by a virus. The rabies virus is present in the saliva glands of infected animals, and if an infected animal bites a person or another animal, the rabies virus will be passed on through the saliva.
Many people associate rabies with dogs. But any warm-blooded animal can get rabies, including foxes, skunks, bats, coyotes, and wolves. And a bite from one of these infected creatures is just as bad as a bite from a rabid dog.
Even a cat can sometimes carry rabies!