(CBS) — The PAWS facility in southwest suburban Tinley Park and the has been shut down because of dog flu and the Chicago Animal Care and Control facility has also been affected..

Chicago Animal Control shut down adoptions on Friday after learning 21 dogs at the facility tested positive. All are undergoing treatment and the rest are quarantined.

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CACC is working with a veterinary team from the University of Wisconsin, and the building, at 2741 S. Western Av., is undergoing deep cleaning.

CACC Director Sandra Alfred is asking those thinking about bringing a dog to the facility to hold off, if possible.

“We have had adoptions at CACC nearly every single day of the year for at least the last ten years, and we intend to resume adoptions as soon as it is safely possible to do so,” Alfred said.

While CACC is still transferring some dogs to other agencies, that is being done at a pace that is slower than the usual.

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The PAWS shelter confirms there are 35 confirmed cases of dog flu at the location. The first case of a sick dog was three to four days ago.

PAWS is expected to stay close for at least another 10 days.

“Only the volunteers that come in to take care of the animals are allowed inside but nobody from the public because we aren’t doing any adoptions or taking in any animals either,” said Peggy Grimm, a volunteer and PAWS board member.

Grimm says they have no idea how the flu was brought into the shelter, but she says it’s not the first time they’ve had to close as a precaution for a medical issue.
“We had an upper respiratory (issue) several years ago and we did close for about a week,” she said.

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Grimm says they are advising pet owners to keep their dogs at home.