Kennel cough or tracheobronchitis is a very easily caught dog illness. The dogs have swelling and pain of the upper breathing passages. It can be caused by viral infections such as canine distemper, canine adenovirus, canine parainfluenza virus, or canine respiratory coronavirus, or bacterial infections such as "Bordetella bronchiseptica". It is called kennel cough because the infection can spread very quickly among dogs, who live together as in a kennel or an animal shelter.