Distemper is a viral disease, which affects the gastrointestinal, respiratory, and central nervous systems in dogs. The canine distemper virus (CDV) causes the disease. It is highly contagious, and is often fatal.
While canine distemper is found around the world, vaccinations have greatly reduced the number of deaths attributed to it. Puppies between the ages of three and six months are the most susceptible to the disease, and are more likely to die than an infected adult dog.
The typical distemper sufferer is a dog who has not received the proper vaccinations. These are usually rescue dogs, or dogs from a pet shop.
The CDV virus can be transmitted through the urine and feces of infected dogs, but the primary method of transmission is through airborne viral particles breathed in by the dog. Dogs in the recovery phase of the disease may continue to shed the virus for several weeks, although once they are fully cured, the danger of infecting others is past. The CDV virus is susceptible to most disinfectants, so routine cleaning of the living quarters of infected dogs will minimize the spread of the disease.
Humans can contract an asymptomatic CDV infection, but if they have been immunized against measles, they are protected from CDV as well.
The earliest symptom of the disease is a fever, followed closely by a runny nose, loss of appetite, and a mild eye discharge. Then, depending on the strain of the infecting virus and the dog’s overall health, the dog could also experience:
• Continued fever
• Pneumonia (Characterized by labored breathing and coughing)
• Depletion of white blood cells
• Hardening of the pads of the feet
• Unusual tooth enamel
Secondary bacterial infections often exacerbate these symptoms. Dogs usually develop an inflammation of the brain and spinal cord, the symptoms of which are varied and progressive.
Dogs can die from distemper; those that do are usually followed by neurological complications, such as the following:
• Ataxia, an inability to coordinate the muscles
• Hyperesthesia, a heightened sensitivity to sensory stimuli, like touch and pain
• Myoclonus, disabling muscle spasms
• Paralysis, partial or complete
• Deterioration of mental abilities and motor skills
• Seizures affecting any part of the body. One memorable type of head seizure that is unique to distemper is sometimes called “the chewing gum fit” because the dog appears to be chewing gum.
Diagnosing distemper infection
It is very difficult to diagnose distemper. Tests for distemper sometimes return a false positive result, and there are many diseases with similar symptoms. A test of the dog’s cerebral spinal fluid will provide a definitive diagnosis, but this test is expensive and can be dangerous for your dog. Most veterinarians rely on a clinical diagnosis: they check for symptoms, perform routine tests, and rule out other diseases by taking a complete history of the dog, including his vaccination schedule, etc.
Unfortunately, there is no specific drug that will cure distemper. The best treatment option at this time is to give supportive care for the different symptoms and to help prevent new infections occurring while the white blood cells are suppressed. A few examples of supportive treatment follow:
• Antibiotics to help prevent pneumonia
• IV fluids to replace fluids lost due to diarrhea and vomiting
• Anti-seizure medication
• Steroids (used only with severe seizures that cannot be controlled with regular medication)
• Preventing infection
Preventing distemper infection is as easy as taking your dog to the veterinarian for a vaccines. The “distemper shot” is generally combined with vaccines for canine parvovirus, parainfluenza, adenovirus 2, leptospirosis, and sometimes coronavirus. Puppies receive a series of vaccines, beginning when they are six to eight weeks old, and then every four weeks until they are 16 weeks old. The next vaccine should be administered one year later, with boosters every one to three years after that.