LANSING, Mich. (AP) — Michigan officials are raising concerns about an outbreak of dog flu in the southern part of the state.

The Department of Agriculture and Rural Development says there have been 49 confirmed cases of canine influenza since mid-July. They’ve occurred in Huron, Kent, Macomb, Oakland, Ottawa and Wayne counties. Only nine cases were reported statewide in all of 2017.

Canine influenza is a highly contagious respiratory infection in dogs, caused by a virus. Signs can include fever, lethargy, coughing and discharges from the nose and eyes.

Most cases are mild, and affected dogs usually recover within a few weeks. But more serious cases can happen.

Michigan State Veterinarian James Averill says there’s a risk of spreading influenza any time dogs gather in groups.