Rabies: Transmission, Symptoms, Treatment, Prevention

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.

Rabies

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 are rare (only one to three cases are reported each year, according to the Centers for Disease Control and Prevention). 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 area around 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.

How is rabies treated?

Rabies is both prevented and treated with a rabies vaccine. The rabies vaccine is made from killed rabies virus. The vaccine cannot cause rabies. Current vaccines are relatively painless and given in the arm similar to other common vaccines.

A special immune globulin can also be helpful in some cases. When it is useful; starting early is important. A medical professional can help you determine if rabies immune globulin is appropriate for your case.

To treat rabies:

If you have been bitten by an animal or exposed to rabies, call your doctor and go to a nearby emergency room immediately. Once there, the doctor will clean the wound thoroughly and give a tetanus shot if you are not up-to-date with your tetanus immunization.

The decision to treat rabies right away by beginning a series of rabies vaccine shots will be based on a number of factors. These include:

• The circumstances of the bite (whether the bite provoked or unprovoked).
• The type of animal (wild or domestic; species of animal).
• The animal's vaccination history (whether or not it is vaccinated).
• Any recommendations from local health authorities regarding the circumstance surrounding the bite.

How dangerous is rabies if it is not treated?

Rabies is almost always fatal if it is left untreated. In fact, once someone with rabies starts experiencing symptoms, they usually do not survive. This is why it is very important to seek medical attention right away following an animal bite, especially if the bite is from a wild animal.

Is the rabies vaccine safe?

The risk of the vaccine causing serious harm is very small. Current vaccines used in the United States cause fewer bad reactions than previous rabies vaccines. Typical mild problems include soreness, redness, swelling, or itching at the sit of the shot. Other mild problems can include headache, nausea, abdominal pain, muscle aches, and dizziness.

More moderate to severe vaccine side effects include hives, joint pain, and fever. Signs of a severe allergic reaction include difficulty breathing, hoarseness or wheezing, hives, paleness, weakness, rapid heartbeat, or dizziness. Waiting in the doctor’s office or emergency area for 30 minutes after a vaccine will usually provide time to see if a severe allergic reaction will occur. If you experience any moderate to severe side effects, call your doctor right away.

How can I prevent rabies?

People at high risk of exposure to rabies should get the rabies vaccine before they come in contact with animals that might have rabies. Such people include veterinarians, animal handlers, and all rabies healthcare and scientific workers. Other people should consider pre-exposure vaccination. This group includes people whose activities bring them in frequent contact with animals that could be rabid. Also, international travelers who may visit parts of the world where rabies is common should get a pre-exposure vaccine.

The pre-exposure vaccination schedule consists of 3 doses, given as follows:

• First dose given.
• Second dose given 7 days after first dose.
• Third dose given 21 days or 28 days after first dose.

If the decision is made to begin the rabies vaccine shots and you have never been vaccinated against rabies:

• You should get 5 doses of the rabies vaccine – first dose immediately, then additional doses 3, 7, 14, and 28 days after the first dose.
• You should also get a shot of Rabies Immune Globulin at the same time as the first dose of rabies vaccine.

If you have been previously vaccinated against rabies:

• You should get 2 doses of the rabies vaccine – the first dose immediately, and the second dose 3 days later.
• You do not need to get a shot of Rabies Immune Globulin.

What other steps can I take to reduce the chance of exposure to rabies?

• Make sure your pets are up-to-date with their rabies vaccines. Consider keeping them indoors so that they are less likely to be bitten by other animals that may be infected with rabies.
• Remind your children never to touch or feed stray dogs, cats, or other animals wandering in your neighborhood or elsewhere. Animals infected with rabies act differently than healthy animals (although in early stages of rabies, they may not show any signs but can still infect you). Wild animals may act tame or move slowly. Other signs of rabies in animals include aggressiveness, increased drooling, problems swallowing, general sickness, difficulty moving/paralysis, and any change from typical animal behavior.
• Notify your local animal control officers or local health authorities if you see any animals that are behaving in a way that suggests they may have rabies.

What are the immediate steps I need to take in case of an animal bite?

• Wash the bite area with soap and water for 5 to 10 minutes.
• Cover the bite area with a clean bandage.
• Call your doctor and go to a nearby emergency room.
• If you know the animal’s owner, get all the information about the animal, including vaccination status and owner's name and address. Call your local health department, especially if the animal hasn't been vaccinated.
• If you don't know the animal’s owner or if a wild animal bites you, immediately call your local animal control authorities to get help finding the animal that caused the bite. The animal will need to be confined and observed for signs of rabies.