RIVERSIDE, Ill. (WLS) -- Dog owners in west suburban Riverside are being told to watch out for zombie raccoons. However, they're not limited to Riverside - they are a persistent problem in Cook County.
"They've been in the Chicagoland area for a long time. They're really all over the Chicagoland area, people should really be aware of their surroundings," said Natalia Derevyanny, a spokesperson with Cook County's animal and rabies control.
The animals carry the distemper virus, which can be lethal to dogs. Riverside police said they have seen an increase in cases of canine distemper virus found in raccoons.
The zombie description refers to the way infected raccoons walk on their hind legs, stagger and bare their teeth.
"It seems every year around this time we get a rise in calls about raccoons acting oddly and we respond to calls about raccoons that may be a danger to the public," said Riverside Police Chief Tom Weitzel. "Our policy allows us to put down animals that are suffering or pose a threat to public safety."
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Police ask pet owners to vaccinate their dogs and supervise them while they are outside, even in a fenced-in yard.
"We've had a number of cases concerning raccoons with distemper in our jurisdiction," Weitzel said "If you see a sick raccoon that may be a threat to public safety, call the police."
Symptoms of the distemper virus include ocular and nasal discharge, sneezing, coughing, lethargy, loss of appetite, vomiting, diarrhea, tremors and seizures, police said.
Zombie raccoons reported in Riverside, a 'persistent problem' across Cook County, officials say