(Q&A below)

Distemper is classically associated with a nasal discharge as shown. Image Courtesy of Dr. Craig Datz.

Most of us have heard of distemper infection for dogs and gather it is bad. The basic vaccine for dogs is commonly referred to as “the distemper shot,” though it also covers several infections besides distemper. Luckily, this is all most people ever hear of distemper. Thankfully, first-hand experience with this horrible disease has become limited because of widespread vaccination. If you are reading this, however, you probably have a dog that is suspected of having this dreaded infection.

The typical distemper suspect is a rescue or pet store dog or puppy, usually with questionable vaccination history or an as yet incomplete vaccination series. The dog or puppy has been housed with other rescue dogs or with a group of dogs/puppies that have been shipped together.

Symptoms begin with:

• Gooey eye and nose discharge
• Fever, which often comes and goes unnoticed
• Poor appetite
• Coughing and development of pneumonia

The virus attacks the interfaces of the body with the environment (the mucous membranes) and starts with the respiratory tract, hence the pneumonia, but it does not stop there. The virus moves on to produce:

• Vomiting and diarrhea
• Callusing of the nose and foot pads (hence one of the old names for distemper – "hard pad disease").

After completing what is called the mucosal phase of infection, where environmental interfaces are attacked (as described by the above GI and respiratory disease), the virus proceeds to the central nervous system for its neurologic phase, leading to:

• Seizures, classically starting with snapping or tremors of the jaws that progress to convulsions of the whole body. This distemper classic sign is called a "chewing gum fit.*