Dog Flu On the Rise

CHICAGO (AP) — Experts say doggie day care contributed to an outbreak of dog flu in Chicago that is spreading in the Midwest.

The illness is believed to be caused by an Asian viral strain, which could arise in other U.S. urban areas. In Chicago, it gained a foothold in the doggie day care centers and got an extra boost from spring break when pets were boarded in kennels.

Experts at Cornell University's College of Veterinary Medicine say the H3N2 dog flu virus likely arose from viruses circulating in live bird markets in Asia. Before now, the strain hadn't been seen in North America. That suggests a recent introduction from Asia.

Not all infected dogs show symptoms. Some get a cough, runny nose and fever. Severe cases can lead to pneumonia and death.