Most of us who have boarded our dogs have, at one time or another, dealt with kennel cough. According to local veterinarians, in the Winnetka (IL) area, kennel cough has been on the rise this summer and fall.

Kennel cough is an upper respiratory illness caused primarily by a bacteria called Bordetella bronchiseptica. However, kennel cough can also be caused by viruses, such as canine distemper, canine adenovirus, canine parainfluenza virus, or canine respiratory coronavirus. Kennel cough is marked by a severe chronic cough, usually dry and hacking, sometimes with nasal discharge. Sometimes there’s a fever associated with the cough.

It’s highly contagious and is spread through the air by dogs coughing or sneezing near other dogs, such as in a kennel, pet store, shelter, grooming facility or doggy daycare. It can be treated with antibiotics and cough suppressants. Vaccination can prevent some strains of it.

However, not all of the cases turned out to be kennel cough. They’re actually a dog flu, a more serious viral infection.

Dog flu, according to the American Veterinary Medical Association, is caused by the same virus that causes equine influenza. Greyhounds at a track in Florida were the first to be diagnosed in 2004, and cases have been turning up in other states since then, including Illinois this summer. It’s spread the same way as kennel cough.

Symptoms of mild dog flu are the same as kennel cough, such as either a dry, hacking cough or a moist cough, which last 10 to 30 days, according to the AVMA.

But, severe dog flu, according to the association, can lead to death. Symptoms of severe dog flu include a high fever, trouble breathing and pneumonia. Pneumonia may also be caused by a secondary bacterial infection, according to the AVMA.

All dogs exposed to it will become infected, according to the AVMA, with 80 percent developing clinical signs. However, according to the association, the other 20 percent, although not showing signs, can still spread it.

Unlike kennel cough, there isn’t a vaccine for dog flu. Although antibiotics don’t work against viruses, they’re being prescribed anyway to help fight off the bacterial infections.