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The County of DuPage
Wheaton, Illinois

Rabies Facts

What causes Rabies?

Rabies is caused by a virus. The virus is transmitted via saliva contact with broken skin or mucous membranes. This normally occurs via a bite from an infected animal.
All warm-blooded (homeothermic) animals can get the disease. The carriers of rabies in the midwest are skunks and bats. Though rodents and birds can get the disease, there has never been a documented case of these animals spreading rabies, mainly because they are usually quickly killed by a bite from another animal.

When the virus is contracted, it enters the nerves at the sight of the bite. Because the immune system is not very active within the nervous system, the body is not able to make rabies antibodies quick enough to attack the virus and stop the disease.

How does the disease progress?

The virus lies dormant in the nerves for a period of time that varies from a few days to months. This is called the incubation period. If treatment is sought immediately and received during the incubation period, recovery is likely. The incubation period in humans averages 60 days.
After the incubation period, the virus travels through the nerves to the brain. This is when symptoms first appear. Death occurs within a few days of the onset of symptoms.

What are the symptoms of rabies?

Rabies affects the nervous system. Easily identifiable symptoms in animals include unusual behavior. Wild animals may act aggressively towards inanimate objects or lose their fear of humans and act friendly.
"Foaming at the mouth" may be present during the later stages of the disease, or not at all. "Foaming at the mouth" is caused by excessive drooling, throat muscle spasms or paralysis, and involuntary jaw movements that turn excessive drool into foam.

Early symptoms in humans include pain or numbness at the sight of the bite, fever, sore throat, nausea, vomiting, abdominal pain, lethargy, depression, apprehension, anxiety, insomnia, and/or agitation and aggressive behavior. Symptoms rapidly progress to include paralysis, throat spasms, delirium, hallucinations, coma, irregular heartbeat (cardiac arrhythmia), and death.

What is the treatment for rabies?

People who have been bitten by a rabid animal are given a series of five rabies vaccinations and a single injection of rabies immune globulin (rabies antibodies). This treatment is considered to be 100% effective when administered within 14 days of rabies exposure.
In the event of a rabies exposure, immediately flushing a bite wound with soap and water for five minutes will greatly reduce the chance of infection.

What is the incidence of rabies in DuPage County?

The incidence of rabies in DuPage County is very low. The last confirmed case of rabies in a wild animal was in 1989. There has not been a case of rabies in a domestic animal in over 50 years. No human has ever contracted the disease in our county.
There are different strains of the virus that tend to infect different species. The carriers of rabies in the midwest are skunks and bats.

How is rabies controlled?

The spread of rabies is most effectively controlled by vaccinating domestic animals against the disease. All dogs and cats in DuPage County are required by law to be currently vaccinated against rabies.
All animal bites to humans that occur in DuPage County must be reported to our office. By law, any time a domestic animal bites a human in DuPage, it must be observed by a licensed veterinarian for rabies**. The owners of biting animals are notified of this responsibility by DuPage County Animal Care and Control. Veterinarians notify us when owners bring their animals in for the observation. Owners who do not comply are cited and must appear before a judge to answer the charge. Fines start at $50.00.

Any time a wild animal bites a human in DuPage, it must be euthanized. A sample of brain tissue is transported to the Illinois Department of Public Health virology lab to be tested for the presence of the virus.

**Bites by birds, caged rabbits, caged rodents (mice, rats, gerbils, hamsters, guinea pigs, etc.) and currently-vaccinated police and registered guard dogs that bite in the line of duty, do not require a rabies observation.

How often am I required to get my pet vaccinated against rabies? 

  • Cats and dogs over 4 months of age must be vaccinated against rabies once a year. Three-year vaccinations are also available.
  • You will receive a rabies vaccination certificate and a rabies tag from your veterinarian. This is your rabies registration. Keep your certificate in a safe place. It is your proof of rabies vaccination status.
  • Attach the tag to your pet's collar for identification and proof of vaccination. Your pet must wear the tag anytime it is off your property.

Citations for failure to vaccinate your pet, register your pet, or display your pet's rabies tag require a court appearance. Fines start at $50.00.
There are also rabies vaccines approved for ferrets, horses, swine, sheep, and cattle. While not required by law, they could save your pet's life.


Bernard, KW, 1990, "Clinical Rabies in Humans," in WG Winkler, ed., Rabies Concepts for Medical Professionals, Merieux Institute, Miami FL.
Murphy, FA, 1990, "The Rabies Virus and Pathogenesis of the Disease," in WG Winkler, ed., Rabies Concepts for Medical Professionals, Merieux Institute, Miami FL.

Protecting Yourself from Rabies, 1991, Connaught Laboratories, Inc., Swiftwater, PA.