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Rabies

By

The Manual's Editorial Staff

Last full review/revision Sep 2020| Content last modified Sep 2020
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What is rabies?

Rabies is a deadly viral infection that causes inflammation of the brain and spinal cord (encephalitis) in people and in animals.

  • The most common way to get rabies is to be bitten by an infected animal (bat, raccoon, skunk, fox, dog, cat)

  • The risk of an animal carrying the rabies virus depends on the type of animal, whether it is wild or a pet, and where it lives

  • If you were bitten by an animal, you should go to a doctor right away to see whether you need rabies shots

  • Symptoms usually appear 30 to 50 days after being bitten

  • If you get rabies shots right after being bitten, you almost never get rabies

  • Once you have symptoms, no treatment can help and you will likely die

What causes rabies?

Rabies is caused by the rabies virus. The virus is common in certain wild animals. Rabies virus is in the saliva (spit) of an infected animal so it can be passed on by a bite. Animals that have had rabies shots almost never get rabies, so they can't give rabies to people.

In the United States, the most common cause of rabies is a bite from:

  • Bats

You may not notice a bat bite, so visit your doctor if you think you may have been bitten, such as if you woke up with a bat in your room.

Other animals that spread rabies in the United States include raccoons, skunks, and foxes. Birds and reptiles do not carry rabies. Rodents (such as rats and mice), squirrels, and rabbits have not spread rabies to people.

Most pets in the United States have been given rabies shots, so they almost never cause rabies in people. However, in places where dogs are not given rabies shots, dog bites are the most common cause of rabies. Such places include Latin America, Asia, and Africa.

What are the symptoms of rabies?

Symptoms usually do not start until 30 to 50 days (sometimes as few as 10 days) after being infected. You may feel:

  • Pain and numbness where you were bitten

  • Fever and headache

  • Sick all over

  • Restless, confused, and uncontrollably excited

  • Like you have too much saliva in your mouth

  • Painful muscle spasms in your throat and trouble swallowing, speaking, and breathing

Eventually, your brain infection gets so bad that you die.

How can doctors tell if I have rabies?

Doctors look at your symptoms and ask about animal bites.

Doctors do tests to look for the virus, including:

  • Skin biopsy (taking a piece of skin from the back of your neck to look at under a microscope)

  • Saliva test

  • Spinal tap (using a long needle to get spinal fluid from your lower back)

How do doctors treat rabies?

Prevention is the best treatment because after rabies symptoms start, no treatment can stop the disease. Doctors do treat the symptoms to make people more comfortable.

How can I prevent rabies?

  • Avoid animal bites by not going up to wild animals or pets that you don't know

  • If you work with animals, get the rabies vaccine in case you're exposed to the rabies virus

If an animal bites you, clean the wound with plenty of soap and water and go to the doctor right away. The doctor will clean your wound some more.

Doctors will ask about the animal that bit you and the circumstances of the bite to see if you're at risk of rabies. Some risk factors include:

  • Wild animal, particularly a bat, fox, skunk, or raccoon

  • Animal acting sick or behaving strangely

  • Pet animal that hasn't had shots or owner can't be found

  • Rabies in many wild animals in your area

If doctors think you're at risk, they'll give you:

  • An injection of rabies immune globulin around the bite

  • Rabies vaccine, one dose right away and several more over the next few weeks

Rabies immune globulin attacks any rabies virus in your system and gives short-term protection. Rabies vaccine gets your immune system to attack the virus.

If you were bitten by a dog or other pet that had no symptoms of illness, and the pet can be observed by the owner or a vet, doctors may wait 10 days to see if the animal develops symptoms of rabies. If the animal is healthy after 10 days, it didn't have rabies when it bit you. If the animal gets symptoms, you'll be treated.

People who get the immune globulin and all the vaccine shots soon after being bitten almost never get rabies.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Gammagard S/D
NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
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