What is rabies?

Rabies is a serious disease that is caused by a virus. It is mainly a disease of animals, but humans can get rabies when animals infected with the disease bite them. The virus is transmitted to humans through the infected animal's saliva. Very rare cases occur when infected saliva gets into someone’s eyes or mouth or into an open wound.

Infected wild animals – especially bats, but also skunks, raccoons, foxes, and coyotes – typically transmit the disease to humans. In the United States, dogs rarely transmit rabies to humans; however, outside the United States, infected dogs are the most common source of transmission to humans. Any mammal (i.e., warm-blooded animal with fur) can get rabies. Animals that are not mammals (e.g., birds, fish, snakes) cannot get rabies.

The number of human cases of rabies in the United States is very low (fewer than 40 cases since 1990, according to the Centers for Disease Control and Prevention), but as many as 40,000 people are treated each year for possible exposure to rabies after animal bites. Worldwide, rabies kills between 40,000 and 70,000 people each year and millions of animals.

If you are bitten by an animal, you should seek medical advice about possible post-exposure treatments.

What are the symptoms of rabies?

Symptoms can appear as soon as a few days after being bitten by an infected animal. However, in most cases, symptoms may not appear until weeks or months later.

One of the most unique symptoms of rabies infection is a tingling or twitching sensation in the muscle tissue around the area of the animal bite. After the virus leaves the local bite area, it travels up a nearby nerve to the brain and can cause such symptoms as:

  • Pain.
  • Fatigue.
  • Headaches.
  • Fever.
  • Muscle spasms.
  • Irritability.
  • Excessive movements.
  • Agitation, aggressiveness.
  • Confusion.
  • Seizures.
  • Bizarre or abnormal thoughts.
  • Hallucinations.
  • Weakness, paralysis.
  • Increased production of saliva or tears.
  • Extreme sensitivity to bright lights, sounds, or touch.
  • Difficulty speaking.

At advance stages of the infection (when the infection spreads to other parts of the nervous system), the following symptoms can develop:

  • Double vision.
  • Problems moving facial muscles.
  • Abnormal movements of the diaphragm and muscles that control breathing.
  • Difficulty swallowing and increased production of saliva, causing the "foaming at the mouth" usually associated with a rabies infection.