In 2015, it showed up in Chicago, tearing through kennels, veterinary clinics and animal shelters. “In the shelter setting, flu is not super subtle because it comes in like a tidal wave,” said Dr. Sandra Newbury, who directs the University of Wisconsin Shelter Medicine Program. (Dr. Newbury, who was part of the team that responded to and studied the Chicago outbreak, has also been working with Operation Kindness in recent weeks.)