Rabies
is an infection caused by a virus that is almost always fatal unless it is treated before symptoms appear. It affects the central nervous system.
People usually contract rabies through a bite or scratch from an infected animal. Animals in the United States that commonly carry the virus include bats, raccoons, skunks, foxes, and coyotes. Dogs and cats can also carry the disease. The rabies virus is found in the saliva, brain, or nervous tissue of infected animals.
In the US, rabies in humans is rare, with fewer than 50 cases diagnosed since 1990. However, 16,000-29,000 people are treated each year with rabies vaccine for possible exposure after animal bites.
Rabies symptoms include:
- Pain, tingling, or itching at the site of the bite wound or other site of viral entry
- Stiff muscles
- Increased production of thick saliva
- Flu-like
symptoms, such as headache, fever, fatigue, and nausea
- Painful spasms and contractions of the throat when exposed to water (called "hydrophobia")
- Erratic, excited, or bizarre behavior
- Paralysis
Symptoms may not appear for weeks, or even years, after a bite.
If an animal has bitten you, immediately wash the wound with plenty of soap and water and call your doctor or seek care in an emergency room. People who may have been exposed to rabies will be treated with one dose of immune globulin and five doses of rabies vaccine over a 28-day period.
The rabies vaccine is made from killed rabies virus. It is given by injection and should be stored in the refrigerator prior to administration.
There are two reasons for rabies vaccines: preventive vaccination and vaccination after exposure.
Preventive vaccination is suggested for people at high risk of exposure to rabies (eg, veterinarians, animal handlers, rabies laboratory workers, spelunkers, rabies biologics production workers). The vaccine should also be considered for people whose activities bring them into frequent contact with the rabies virus or potentially rabid animals, as well as international travelers who may come into contact with rabid animals.
Preventive vaccination is given in three doses, with the second dose given seven days after the first, and the third given 21 or 28 days after the first. People who may be repeatedly exposed to the rabies virus should be periodically tested for immunity and given booster doses as needed.
Vaccination after exposure is given to anyone who has been bitten by an animal or was otherwise exposed to rabies. This regimen includes five doses of rabies vaccine—one immediately and four more doses on the third, seventh, fourteenth, and twenty-eighth days. Also, a shot of rabies immune globulin should be given along with the first dose of vaccine. For people who have been previously vaccinated, two doses of the vaccine are given, one immediately and another on the third day. Rabies immune globulin is not needed for those previously vaccinated.
Like any vaccine, the rabies vaccine is capable of causing serious problems, such as severe allergic reactions, but the risk of serious harm or death is extremely small.
The most commonly reported problems associated with the rabies vaccine are mild to moderate and include soreness, redness, swelling, or itching around the injection site; headache; nausea; abdominal pain; muscle aches; dizziness;
hives
; pain in the joints; and fever. Rarely, an illness resembling
Guillain-Barre syndrome
and other nervous system disorders has been reported in association with the vaccine.
People who have had a life-threatening allergic reaction to a previous dose of rabies vaccine or one of its components and people who have a weakened immune system (eg, due to a disease, drugs, or
cancer
) should talk with their doctor before getting vaccinated.
Also, people who are moderately or severely ill should wait until they recover before getting a preventive vaccine. But people who have been exposed to the rabies virus should get the vaccine regardless of any other illness they have.
Here ares some ways to prevent rabies:
- Vaccinate house pets.
- Avoid contact with wild animals.
- Do not touch any wild animal, even if it appears to be dead.
- Seal basement, porch, and attic openings to prevent an animal from entering your home.
- Report strangely acting or sick animals to local animal control authorities.
Rabies symptoms in animals may include erratic behavior (often overly aggressive or vicious) or disorientation (eg, nocturnal animals such as a bat or fox appearing in daylight).
In the event of a rabies outbreak, authorities will identify and control the source of the outbreak. They will also increase their surveillance of wild and domestic animals. Steps will be taken to increase animal rabies vaccination rates and provide safety education to the public.
