Chicago dog with rabies marks first positive test in Cook County in decades

A dog in Chicago tested positive for rabies, marking the first time in than 60 years that a dog tested positive for the disease in Cook County.

The dog, vaccinated for rabies in June, showed a shift in behavior last week and was euthanized before testing positive, the Cook County Department of Animal and Rabies Control said in a statement.

The case is the first positive test in Cook County since 1964, and the first in Illinois since 1994, the agency said.

The source of rabies in the dog wasn’t immediately known. And it’s unclear how a vaccinated dog contracted the disease.

The Chicago Department of Public Health “is reviewing how a vaccinated dog contracted rabies and will share findings as they become available,” Animal and Rabies Control said in the statement. “This investigation will inform public education efforts to prevent future cases.”

The dog, born in Georgia, was taken to a Chicago rescue shelter and adopted by a Chicago family, the agency said. Thirteen people who had contact with the dog have not shown symptoms and are being given preventative treatment. The risk to the public and their pets is low, the department said.

The Chicago Department of Public Health and Illinois Department of Public Health are also investigating the cause of the positive case, according to the statement.

Rabies is a fatal but preventable viral disease that causes madness and convulsions, health officials said. It spreads though saliva from an infected animal to people, most commonly through a bite. Rabies can also spread by saliva though open wound or the eyes, nose or mouth. It can take weeks to over a year for a rabies exposure to become an infection.