Rabies
Rabies is an illness you get from an infection with the RABV virus. It causes symptoms like seizures, hallucinations and paralysis. The most common way to get rabies is through bat bites (in the U.S.) or dog bites (in Asia and Africa). Rabies is preventable if you’re vaccinated quickly after exposure. Once symptoms start, rabies is fatal.
What is rabies?
What happens when you get rabies?
Rabies virus gets into your body when the saliva (spit) of an infected animal gets into an open wound (usually from a bite). It moves very slowly along nerves into your central nervous system (your brain and spinal cord). When it reaches your brain, the damage causes neurological symptoms. From there, rabies leads to coma and death.
Who does rabies affect?
Rabies is most common in rural parts of Asia and Africa, though it’s found on all continents except Antarctica. In the U.S., rabies is commonly found in wild animals. But dogs carry rabies in many other countries. Children are more likely to get rabies than adults.
Rabies moves from an infected wound to your brain over time. There are several phases that most people go through: incubation, prodromal phase, acute neurologic phase and coma.
Incubation
Rabies virus can spend days to weeks in your body before it gets into your nervous system (incubation). You don’t have any symptoms during this time. If you receive treatment early in the incubation period, you won’t get rabies.
Prodromal phase
RABV travels through your nerve cells into your brain and spinal cord, causing nerve damage as it goes. The prodromal phase starts when the rabies virus has entered your nervous system. Your immune system tries to fight back, causing flu-like symptoms. Nerve damage might cause tingling, pain or numbness where you were bitten. This lasts two to 10 days. There aren’t any effective treatments when rabies reaches this phase.
Acute neurologic phase
In this phase, the rabies virus starts damaging your brain and spinal cord. About two-thirds of people have furious rabies, with symptoms like aggression, seizures and delirium. Others have paralytic rabies, with weakness and paralysis progressing from the bite wound to the rest of their body. Furious rabies can last a few days to a week. Paralytic rabies can last up to a month.
Coma
Many people enter a coma in the final stages of a rabies infection. Rabies eventually leads to death.
SYMPTOMS AND CAUSES
You usually have no symptoms of rabies for several weeks after it enters your body. When rabies makes it to your central nervous system (prodromal phase), you experience flu-like symptoms. In the final stages, you have neurological (brain) symptoms.
Prodromal symptoms of rabies
- Fever.
- Tiredness (fatigue).
- Bite wound burning, itching, tingling, pain or numbness.
- Cough.
- Sore throat.
- Muscle pain.
- Nausea and vomiting.
- Diarrhea.
Acute neurologic symptoms of rabies
Neurological symptoms of rabies are either furious or paralytic. Furious rabies symptoms may come and go with periods of calm in between (furious episodes).
Furious rabies symptoms
- Agitation and aggression.
- Restlessness.
- Seizures.
- Hallucinations.
- Muscle twitching (fasciculations).
- Fever.
- Racing heart (tachycardia).
- Fast breathing (hyperventilation).
- Excessive salivation.
- Two different-sized pupils (anisocoria).
- Facial paralysis (facial palsy).
- Fear of water/drinking (hydrophobia).
- Fear of air being blown in your face/drafts (aerophobia).
- Delirium.
Paralytic rabies symptoms
- Fever.
- Headache.
- Neck stiffness.
- Weakness, especially starting from the body part that was bitten and progressing to other body parts.
- Tingling, “pins and needles” or other strange sensations.
- Paralysis.
- Coma.
How do you get rabies?
Rabies is carried by warm-blooded animals (mammals) and collects in their saliva (spit). You usually get rabies through the bite of an infected animal.
Rabies is most commonly found in bats, skunks, raccoons and foxes, but other animals — including your pet dog or cat — can become infected. If a break in your skin comes in contact with the spit of an infected animal, you could get rabies.
Rarely, people have gotten rabies from receiving donated organs.
MANAGEMENT AND TREATMENT
There’s no approved treatment for rabies once you have symptoms. If you’ve been exposed to rabies (were bitten by or been in contact with an infected animal), contact a healthcare provider as soon as possible.
Clean the wound gently but thoroughly with soap and water. Ask your provider for additional instructions on cleaning the wound.
Your provider will give you a series of shots (vaccinations) to prevent the virus from causing rabies. They’ll also give you an antibody treatment directly to the wound if you’ve never been vaccinated before.
If you’re bitten or scratched by a wild animal, there are steps you can take to prevent rabies.
Medications prevent an infection from traveling to your brain if you’ve been exposed to rabies (post-exposure prophylaxis/PEP). These medications are often combined:
- Rabies vaccine. Your healthcare provider will give you four shots over 14 days. If you’ve already been vaccinated before exposure, you’ll only need two shots. The vaccine teaches your body to destroy the rabies virus before it enters your brain.
- Human rabies immune globulin (HRIG). Your provider will give you shots around the wound. HRIG gives you antibodies (molecules that fight infection) that will destroy the virus near the wound until your body takes over. You shouldn’t get HRIG if you’ve been vaccinated before your exposure.
Side effects of rabies treatment
You might have mild side effects of rabies vaccines, including:
- Pain, itching or swelling where you received the shots.
- Nausea.
- Headache.
- Muscle pain.
- Dizziness.
If you have severe side effects, contact your provider.
What should I do if I’ve been bitten by an animal?
If you’ve been bitten or scratched by an animal:
- Wash the wound right away with soap and water. Use a 10% povidone-iodine solution if available.
- Contact a healthcare provider or your department of public health as soon as possible. Tell them what happened and give them as much information as you know about the animal. (Was it a wild animal or a pet? What kind of animal was it? How was it acting?)
- Ask your healthcare provider how best to clean the wound and whether you need a rabies vaccine.
- If you’ve been attacked by an aggressive wild animal, contact animal control.
There’s no cure for rabies once it’s moved to your brain because it’s protected by your blood-brain barrier.
Your blood-brain barrier is a layer between your brain and the blood vessels in your head. Its job is to protect your brain by keeping toxins and other dangerous substances from getting into your brain from your blood. It’s like a very fine strainer.
Researchers aren’t sure how, but rabies locks this barrier down even further, so medications that might destroy it can’t get through.
How can I prevent rabies?
Rabies is preventable. Keeping your pets safe and staying away from wild animals will help prevent you from being exposed to rabies. If you’re exposed, you can get a vaccine to prevent rabies before symptoms start.
- Make sure your pets’ vaccinations are up-to-date. This includes dogs, cats and ferrets.
- Don’t let your pets roam free without supervision.
- Leave wildlife alone. Don’t touch injured animals or try to capture animals yourself.
- If you find a bat in a room where someone was sleeping, assume they’ve been bitten. Bat bites are small and fade quickly, so you might not notice them. Contact a healthcare provider right away.
- If you’re bitten or scratched by a wild animal or have been exposed to rabies in some other way, contact a healthcare provider as soon as possible.
- If you’re at high risk for being exposed to rabies, it’s recommended that you get vaccinated on a regular basis (pre-exposure prophylaxis/PREP).
Pre-exposure prophylaxis (PREP)
If you’re at higher risk for rabies, you should get vaccinated before exposure based on the recommendations of your local health authority. This is called pre-exposure prophylaxis (PREP) and it’s a series of two shots. How frequently you need boosters depends on how high your risk of exposure is.
You’re usually considered higher risk for rabies if you:
- Work with wildlife or domestic animals (this includes veterinarians, veterinary technicians, wildlife biologists, animal control officers and others).
- Are around bats or in caves often.
- Work in a lab where you handle rabies virus.
How long can you live with rabies?
You can live several weeks or months after being exposed to rabies without symptoms. Once symptoms start, rabies causes death within a few days.
It’s common for dogs to have rabies in developing areas of Asia and Africa. In developed countries, including the U.S., Canada and countries of Western Europe, rabies isn’t usually found in domestic (pet) dogs.
Rabies is a serious illness that’s almost always fatal. Fortunately, it’s completely preventable if you’re treated right away. If you’ve been bitten by an animal or think you’ve been exposed to rabies, contact your healthcare provider right away.
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