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Rensimer and Associates is one of only two practices and about 9 facilities in Harris County where HRIG and rabies vaccine and the expertise to appropriately consider their use post-exposure to a rabid animal or pre-exposure (occupational and travel) are available.  Medical insurance payors are increasingly denying payment for these services provided through hospital emergency rooms (and so hospitals are getting out of this business) because of the extreme charges for any ER visit and they do not consider this situation a legitimate medical emergency.  These treatment materials are stocked here and our organization is trained to operationally expedite their application, including evaluating to what extent medical insurers will cover their expense.  Because we daily immunize to rabies (80 – 100 individuals/year), it is highly unlikely an insurer will decline or otherwise contend with our position on the medical necessity of rabies immunization.


  • Rabies is a serious viral infection that spreads from a bite wound through the nerves to the brain and spinal cord.
  • Rabies is an almost invariably fatal.
  • Rabies is mainly a disease of animals. Humans gets rabies when they are bitten, scratched, or licked with infected animal saliva.
  • At first there might not be any symptoms. But weeks, or even years (up to 19) after a bite, rabies can cause pain, fatigue, headaches, fever, and irritability. These are followed by seizures, hallucinations, and paralysis. Human rabies is almost always fatal.
  • Wild animals, especially bats, are the most common source of human rabies infection in the United States. Skunks, raccoons, dogs, cats, coyotes, foxes, and other mammals can also transmit the disease.
  • Human rabies is rare in the United States.
  • There have been only 55 cases diagnosed since 1990.
  • However, between 15,000 and 40,000 people are vaccinated each year as a precaution after animal bites.
  • Rabies is far more common in other parts of the world, with about 40,000 to 70,000 rabies-related deaths worldwide each year (outside the U.S., most commonly due to unvaccinated dogs and cats).
  • The average incubation period from contact with the virus is 2-8 weeks (range is 5 days to 19 years) and treatment to prevent it should be started as medically urgent (though not emergent).


Rabies is caused by a virus that lives inside some animals. When a person is bitten by an infected animal, the rabies virus is spread to the person through the infected spit (saliva) of the animal.

In the U.S., principal vectors are wild animals, especially skunks, raccoons, coyotes, foxes, and bats.  Domesticated animals, like cats and dogs, can carry rabies, but are usually vaccinated against it (and so, usually not a risk).  Dogs are the major vector in foreign countries.  Any unvaccinated or sick animal lick, bite, or scratch, including from livestock and rodents, warrants medical evaluation.


By the time symptoms appear, rabies is virtually 100% fatal for the person. Common symptoms include:

  • Fever
  • Headache
  • Fatigue
  • Agitation
  • Anxiety
  • Confusion
  • Unusual behavior, such as hyperactivity, fear of water (hydrophobia), or fear of air (aerophobia)
  • Hallucinations
  • Insomnia
  • Weakness in the arms or legs
  • Difficulty swallowing
  • Pain or abnormal sensations near the bite site

Most people get sick within 3 months after being bitten. This often varies and may depend on the location of the bite. The clinical illness will take less time to emerge if the bite occurred closer to the head (and so, the brain).


To determine if a person is infected with rabies virus, several tests must be performed after symptoms and signs appear,

  • Skin biopsy (viral staining)
  • Saliva virus test
  • Lumbar puncture to remove spinal fluid so it can be tested for rabies virus
  • Blood tests

Note: There are no lab tests for rabies prior to onset of illness.


Post-rabies exposure treatment with injection of human rabies immunoglobulin (pooled human rabies antibody), called HRIG, and a 4-dose series of rabies vaccine is nearly 100% successful in preventing rabies infection.

If medical experts determine there has been a credible rabies exposure, treatment to prevent the infection from developing (post-exposure prophylaxis, PEP) should be started even before knowing for sure if the person has been truly exposed to the rabies virus.

PEP involves cleaning the wound, giving an antibody injection (rabies immune globulin), and giving a 4-dose series of rabies vaccine injections. The injections are usually given over two-weeks. If possible, the animal that bit the person should be observed to see if it remains healthy (in which case, PEP may be withheld until the animal is cleared or ill). For dogs, cats, and ferrets this is 10 days. For other animals, the proper necessary observation period is unknown. If the animal has been killed, it can be sent to a state laboratory and examined to see if it had rabies (ask medical professionals or public health officials the safe, proper way to handle such an animal specimen).

If a person is bitten by a domestic animal (dog, cat, or ferret) that appears healthy and can be observed to see if it remains healthy, often no further treatment is necessary other than care of the wounds caused by the animal. Rabies is almost always a fatal illness once illness develops, although a few people with rabies have survived after experimental treatments. This is why medical professionals cautiously begin PEP treatment for people who have been bitten by animals that are possibly infected.


If you were bitten by an unknown animal, make sure you know your rabies expert’s instructions for follow-up. If the animal was sent to a laboratory for examination, ask when the test results will be ready. Make sure you get the test results.

Take these steps to care for your wound:

  • Wash the wound thoroughly with soap and water for least 15 min., then with alcohol disinfectant, and then iodine (avoid any spray from the wound cleansing process entering the mouth, nose or eyes).
  • Keep the wound clean, dry, and dressed as directed by your caregiver.
  • Keep the injured part elevated as much as possible.
  • Do not resume use of the affected area until directed.
  • Only take over-the-counter or prescription medicines as directed by your caregiver.
  • Keep all follow-up appointments as directed by your caregiver.


To prevent rabies, people need to reduce their risk of having contact with infected animals.

  • Make sure your pets (dogs, cats, ferrets) are vaccinated against rabies. Keep these vaccinations up-to-date as directed by your veterinarian.
  • Supervise your pets when they are outside. Keep them away from wild animals.
  • Call your local animal control services to report any stray aniamals. These animals may not be vaccinated.
  • Stay away from stray or wild animals.
  • Consider getting the rabies vaccine (preexposure) if you are traveling to an area where rabies is common or if your job or activities involve possible contact with wild or stray animals (especially children). Discuss this with your medical professional.
  • Do not touch a wild, ill, wounded, or dead animal, and instruct your children on this.


Rabies Vaccine

What You Need to Know 


  • Rabies vaccine can prevent rabies.
  • Rabies vaccine is given to people at reasonable risk for rabies to protect them proactively before actual exposure or as a treatment after exposure.
  • Rabies vaccine is made from killed rabies virus. It cannot cause rabies.


Preventive Vaccination (No Exposure)

  • People at high risk for exposure to rabies, such as veterinarians, animal handlers, rabies laboratory workers, spelunkers, and rabies biologics production workers should receive rabies vaccine.
  • The vaccine should also be considered for:
    • People whose activities bring them into frequent contact with rabies virus or with possibly rabid animals.
    • International travelers who are likely to come in contact with animals in parts of the world where rabies is common and animal reservoirs are often not vaccinated.
  • The pre-exposure schedule for rabies vaccination is 3 doses, given at the following times:
    • Dose 1
    • Dose 2: 7 Days after Dose 1
    • Dose 3: 21 days or 28 days after Dose 1
  • For laboratory workers and others who may be repeatedly exposed to rabies virus, periodic blood testing for immunity (rabies antibody) is recommended and booster doses should be given as needed.

Vaccination After an Exposure (Treatment)

Anyone who has been bitten by an animal, or who otherwise may have been exposed to rabies, should clean the wound and see a doctor expert in rabies management immediately. The doctor will determine if they need to be vaccinated. Inexpert healthcare workers and public health officials often give misleading or wrong advice about rabies.

A person who is exposed and has never been vaccinated against rabies should get 4 doses of rabies vaccine: one dose right away and additional doses on the 3rd, 7th, and 14th days. They should also get another shot called Human Rabies Immune Globulin (HRIG, rabies antibody) at or about the same time as the first vaccine dose.

A person who has been previously vaccinated and who has suffered rabies exposure should get 2 doses of rabies vaccine: one right away and another on the 3rd day. HRIG is not needed.


Talk with a doctor before getting rabies vaccine if you:

  • Ever had a serious (life-threatening) allergic reaction to a previous dose of rabies vaccine or to any component of the vaccine; tell your doctor if you have any severe allergies.
  • Have a weakened immune system because of: *
    • HIV, AIDS, or another disease that affects the immune system.
    • Treatment with drugs that affects the immune system.
    • Cancer or cancer treatment with radiation or drugs.

* If your immune system is impaired, you may need an extra vaccine dose(s), as determined by rabies antibody measured in the blood a couple weeks after the last dose.

If you have a minor illness, such as a cold, you can be vaccinated. If you are moderately or severely ill, you should probably wait until you recover before getting a routine (non-exposure) dose of rabies vaccine. If you have been exposed to rabies virus, you should get the vaccine regardless of any other illnesses you may have or pregnancy. With a legitimate exposure to rabies, there is no contraindication to the vaccine or HRIG since infection is fatal.


A vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions. The risk of a vaccine causing serious harm, or death, is extremely small. Serious problems from rabies vaccine are very rare.

Anything that might adversely result from the rabies vaccine or HRIG pales in significance compared to rabies disease.

Mild problems:

  • Soreness, redness, swelling, or itching where the shot was given (30% to 74%)
  • Headache, nausea, abdominal pain, muscle aches, or dizziness (5% to 40%)

Moderate problems:

  • Hives, pain in the joints, or fever (about 6% of booster doses)
  • Other nervous system disorders, such as Guillain-Barré Syndrome (GBS), have been reported after rabies vaccine, but these happen so rarely that it is not known whether they are related to the vaccine

Note: Several brands of rabies vaccine are available in the United States, and reactions may vary between brands. Your provider can give you more information about a particular brand.


What should I look for?

Look for anything that concerns you, such as signs of a severe allergic reaction, very high fever, or behavioral changes.

Signs of a severe allergic reaction can include hives, swelling of the face and throat, difficulty breathing, fast heartbeats, dizziness, and weakness. These would start a few minutes to a few hours after the vaccination.

What should I do?

  • If you think it is a severe allergic reaction or other emergency that cannot wait, call 911 or get the person to the nearest hospital Emergency Department or Emergency Facility.                           
    Call your doctor on the way there or after you arrive.
  • Afterwards, the reaction should be reported to the Vaccine Adverse Event Reporting System (VAERS). Your doctor might file this report, or you can do it yourself through the VAERS website at or by calling 1-800-822-7967.

VAERS is only for reporting reactions. They do not give medical advice.


  • Go to
  • Ask your doctor.
  • Call your local or state health department.
  • Contact the Centers for Disease Control and Prevention (CDC).
  • Visit the CDC rabies website at