Updated: January 4, 2012
Rabies is an acute and deadly disease caused by a viral infection of the central nervous system. The rabies virus is most often spread by a bite and saliva from an infected (rabid) animal (e.g., bats, raccoons, skunks, foxes, ferrets, cats, or dogs). In the United States, rabies is most often associated with bat exposures. However, there have been rare cases in which laboratory workers and explorers in caves inhabited by millions of bats were infected by rabies virus in the air.
Virtually 100% of those infected with rabies who do not receive the vaccine will die. Rabies illness includes rapidly progressing central nervous system symptoms such as anxiety, difficulty swallowing, and seizures.
Although less than ten human rabies fatalities occur in the United States annually, as many as 40,000 Americans receive the vaccine each year after contact with animals suspected of being rabid. An additional 18,000 people get the vaccine before exposure as a preventative measure.
Worldwide, at least 4 million people are vaccinated each year for rabies. The number of deaths that rabies causes each year is estimated to be at least 40,000, and as high as 70,000 if higher case estimates are used for densely populated countries in Africa and Asia where rabies is epidemic. India, with a very large population of stray, ownerless dogs, has about half of all cases of rabies worldwide. Between 30-60% of human rabies cases occur in children under 15 years of age.
Prompt wound care and the administration of rabies immune globulin (RIG) plus vaccine are highly effective in preventing human rabies following exposure.
The rabies vaccine is available as:
Product: Imovax Rabies (HDCV for pre or post-exposure)
Manufacturer: Sanofi Pasteur
Year Licensed: 1980
Product: RabAvert (PCECV for pre or post-exposure)
Year Licensed: 1997
The first rabies vaccine was developed in the early 1960’s. All rabies vaccines currently available for humans are made from killed rabies virus.
Who should receive the vaccine pre-exposure?
Pre-exposure vaccination may be considered for:
Who should receive the vaccine post-exposure?
Pregnant women who are exposed to rabies may receive the vaccine.
Who should not receive the vaccine?
Pre-exposure rabies vaccines are administered by a series of three injections:
When post-exposure rabies vaccines are administered:
There are no controlled trials of rabies vaccine. Among persons who had been bitten by an animal that was proven to be rabid and who received both HRIG and a full course of one of these modern rabies vaccines there have been no cases of rabies. Previously immunized people still must receive two additional doses of the vaccine if exposed to the virus, and the vaccine is almost 100% effective in these cases as well.
Although all rabies vaccines licensed in the U.S. induce protective antibody levels after three doses in nearly 100% of recipients, it is important to complete the dose schedules recommended for individual circumstances (see Dose Schedule). Previously, a 5-dose vaccine schedule was recommended but the dose that was given at 28 days is no longer felt to be necessary.
Mild reactions such as pain, redness, swelling, or itching at injection site are reported among 30%-74% of those vaccinated. Headache, nausea, abdominal pain, muscle aches, and dizziness are reported in 5-40% of those vaccinated.
Serious events after vaccination are rare. However, allergic reactions including swelling and mild difficulty breathing developed in 6% of patients who received booster doses of Human Diploid Cell Rabies Vaccine. In addition, three cases of neurologic illness resembling Guillain-Barré Syndrome, a progressive disorder affecting the nervous system, have been reported in people who received the Human Diploid Cell Rabies Vaccine. In these cases, all patients recovered within three months.
This vaccine is recommended by:
What should you do if bitten by a rabid or suspicious animal?
1) Wash all bites and scratches immediately and thoroughly with soap and water and a solution that kills viruses (such as a povidone-iodine solution). Wound cleansing alone will markedly reduce the chances of getting rabies.
2) Go to a health care provider for a medical assessment regarding the need for a tetanus shot (if it needs to be updated), rabies vaccination, and administration of RIG, human. Two rabies immune globulins are licensed for use in the U.S. Each year approximately 18,000 people in the U.S. receive vaccination and immune globulin, and none of them has developed rabies.
3) Notify the state or local health department.
Vaccination and appropriate immune globulin therapy can protect you after you have been bitten. Vaccination before exposure merely simplifies therapy by eliminating the need for RIG and decreasing the number of vaccine doses needed.
Effective rabies control measures include routine immunization of dogs, cats, and ferrets, and control of stray dogs and selected wildlife. A fully vaccinated dog or cat is unlikely to become infected or to transmit rabies.