Rabies: What You Need To Know

bat in flight

About Rabies

Rabies is a deadly but preventable disease caused by a virus that affects the brain and nervous system. It spreads to people and pets through the saliva or brain tissue of infected animals, usually through a bite. In the United States, deaths due to rabies occur when people fail to seek medical assistance, usually because they are unaware of their exposure to a rabid animal. Rabies is almost always fatal once symptoms appear but can be prevented with timely treatment.

Quick Facts

  • In Chicago, bats are the most common source of rabies. Typically, about 3-4% of tested bats are positive for rabies each year in Illinois.
  • More than 90% of reported rabies cases occur in wildlife in the United States, including bats, raccoons, skunks, and foxes.
  • No dogs have tested positive for rabies in Cook County since before 1964 and no cats have been positive since 1974.
  • The last human case of rabies in Illinois was reported in 2021.

Rabies in People

After a bite, the virus must travel to the brain before it causes symptoms. The time from the bite to symptoms can be weeks to months. Early symptoms of rabies in people may be like the flu, including fever, headache, and general weakness or discomfort. There may also be pain, itching, or discomfort at the site of the bite.

When the disease progresses to the central nervous system, more severe symptoms appear and may include:

  • Insomnia
  • Anxiety
  • Confusion
  • Agitation
  • Paralysis
  • Hallucinations
  • Excess saliva and difficulty swallowing
  • Hydrophobia (fear of water)

Severe disease typically occurs within 2 weeks of the first symptoms. Once symptoms start, rabies is almost always fatal.

Rabies Prevention

  • Never handle a bat with bare hands.
  • Don’t approach wild animals who appear to be injured, sick, or dead, especially if you see them during the day and they’re typically active at night (e.g. bats, raccoons).
  • Keep your pets’ rabies vaccinations up to date. In Chicago, all pet dogs and cats must be vaccinated for rabies by 4 months of age.
  • Rabies Vaccine Ordinance
  • Pet Vaccine Clinic Dates
  • Don’t let your pets come into contact with bats or other wild animals.

Rabies in people is preventable but requires urgent medical help called post-exposure prophylaxis (PEP). PEP is a safe and highly effective way to prevent rabies but should be given as soon as possible after exposure to a rabid animal. PEP is a series of shots typically given over 2 weeks. If you've been in contact with any wildlife or unfamiliar animals, you should:

  • Immediately wash any wounds with soap and water for 15 minutes.
  • Talk with a healthcare provider or public health professional about your risk for rabies and whether you need PEP.
  • Note the type of animal and whether it seemed to be acting normally.
  • If the animal that bit you is a dog, report the dog bite by calling 911 and, if possible, ask the owner for proof that the animal is up to date on their rabies vaccination.

Bats & Rabies Risks

bats in flight

In Chicago, bats are the primary source of human rabies. Although not all bats have rabies, bats found in Chicago and surrounding counties test positive for rabies each year. During 2020–2024, the Illinois Department of Public Health tested 1,191 bats found in Chicago and 14 (1.2%) were positive for rabies.

Bat activity increases in the summer months, especially August, due to migration and feeding patterns.

Bats have very small teeth! Their bites may be painless and hard to see. If you, a family member, or a pet have had contact with a bat or a bat was found in the room of someone who was sleeping or mentally impaired, seek medical care as soon as possible.

Signs of Rabies in Bats

Not all bats carry rabies. Unusual behaviors in bats that could be signs of rabies include:

  • Bats that are active during the day
  • Bats found in unusual places, such as inside a home or on the ground
  • Bats that cannot fly
  • Bats that you can easily approach or that come into contact with people

If you find a bat in your home, it may need to be tested for rabies. If you live in Chicago, call 311 to report the bat to Chicago Animal Care and Control.

Rabies Resources

For the Public

For Healthcare Professionals