How do you know if your dog has rabies?

Rabies in dogs is a neurologic disease that is progressive and fatal. Early signs include changes in behavior. Some dogs that were gentle and placid become aggressive and bite with no provocation - this is called "furious rabies". Other dogs can become very passive and fail to interact with the rest of the world - this is called "dumb rabies". With either form, you often see a lack of ability to control the position of the head, changes in behavior patterns, an absolute aversion to water, and possibly foaming at the mouth. At this stage the dog is both extremely dangerous to humans as well as actively and rapidly dying - the best option is to call animal control and let them contain the dog for a veterinarian to euthanize. Confirmation of rabies infection is done through testing of the brain tissue after death; in the United States this testing must be done by law on all suspected rabies cases.