Rabies — the word probably brings to mind an enraged animal frothing at the mouth. An encounter with an infected animal can result in a painful, life-threatening condition.
According to the World Health Organization, up to 59,000 people worldwide die from rabies every year. Ninety-nine percent of them have been bitten by a rabid dog. However, the availability of vaccines for both animals and humans has led to a steep decline in rabies cases in the United States, where there are two to three rabies deaths a year.
Rabies is caused by a virus that affects the central nervous system, particularly causing inflammation in the brain. Domestic dogs, cats, and rabbits, and wild animals, such as skunks, raccoons, and bats, are able to transfer the virus to humans via bites and scratches. The key to fighting the virus is a quick response.
The period between the bite and the onset of symptoms is called the incubation period. It usually takes four to 12 weeks for a person to develop rabies symptoms once they’re infected. However, incubation periods can also range from a few days to six years.
The initial onset of rabies begins with flu-like symptoms, including:
- muscle weakness
You may also feel burning at the bite site.
As the virus continues to attack the central nervous system, there are two different types of the disease that can develop.
Infected people who develop furious rabies will be hyperactive and excitable and may display erratic behavior. Other symptoms include:
- excess salivation
- problems swallowing
- fear of water
This form of rabies takes longer to set in, but the effects are just as severe. Infected people slowly become paralyzed, will eventually slip into a coma, and die. According to the World Health Organization, 30 percent of rabies cases are paralytic.
Animals with rabies transfer the virus to other animals and to people via saliva following a bite or via a scratch. However, any contact with the mucous membranes or an open wound can also spread the virus. The transmission of this virus is considered to be exclusively from animal to animal and animal to human. While human-to-human transmission of the virus is extremely rare, there have been a handful of cases reported following transplantation of corneas. For humans who contract rabies, a bite from an unvaccinated dog is by far the most common culprit.
Once a person has been bitten, the virus spreads through their nerves to the brain. It’s important to note that bites or scratches on the head and neck are thought to speed up the brain and spinal cord involvement because of the location of the initial trauma. If you’re bitten on the neck, seek help as soon as possible.
Following a bite, the rabies virus spreads by way of the nerve cells to the brain. Once in the brain, the virus multiplies rapidly. This activity causes severe inflammation of the brain and spinal cord after which the person deteriorates rapidly and dies.
Animals that Can Spread Rabies
Both wild and domesticated animals can spread the rabies virus. The following animals are the main sources of rabies infection in humans:
For most people, the risk of contracting rabies is relatively low. However, there are certain situations that may put you at a higher risk. These include:
- living in an area that is populated by bats
- traveling to developing countries
- living in a rural area where there is greater exposure to wild animals and little or no access to vaccines and immunoglobulin preventive therapy
- frequent camping and exposure to wild animals
- being under the age of 15 (rabies is most common in this age group)
Although dogs are responsible for most rabies cases worldwide, bats are the cause of most rabies deaths in the Americas.
There is no test to detect the early stages of rabies infection. After the onset of symptoms, a blood or tissue test will help a doctor determine whether you have the disease. If you have been bitten by a wild animal, doctors will typically administer a preventive shot of rabies vaccine to stop the infection before symptoms set in.
After being exposed to the rabies virus, you can have a series of injections to prevent an infection from setting in. Rabies immunoglobulin, which gives you an immediate dose of rabies antibodies to fight the infection, helps to prevent the virus from getting a foothold. Then, getting the rabies vaccine is the key to avoiding the disease. The rabies vaccine is given in a series of five shots over 14 days.
Animal control will probably try to find the animal that bit you so that it can be tested for rabies. If the animal isn’t rabid, you can avoid the large round of rabies shots. However, if the animal can’t be found, the safest course of action is to take the preventive shots.
Getting a rabies vaccination as soon as possible after an animal bite is the best way to prevent the infection. Doctors will treat your wound by washing it for at least 15 minutes with soap and water, detergent, or iodine. Then, they’ll give you the rabies immunoglobin and you’ll start the round of injections for the rabies vaccine. This protocol is known as “post-exposure prophylaxis.”
Side Effects of Rabies Treatment
The rabies vaccine and immunoglobulin can very rarely cause some side effects, including:
- pain, swelling, or itching at the injection site
- stomach pain
- muscle aches
Rabies is a preventable disease. There are some simple measures you can take to help keep you from catching rabies:
- Get a rabies vaccination before traveling to developing countries, working closely with animals, or working in a lab handling the rabies virus.
- Vaccinate your pets.
- Keep your pets from roaming outside.
- Report stray animals to animal control.
- Avoid contact with wild animals.
- Prevent bats from entering living spaces or other structures near your home.
You should report any signs of an infected animal to your local animal control or health departments.