Distemper (Canine)

GENERAL DESCRIPTION

Canine distemper is a highly contagious, incurable, often fatal, multisystemic viral disease that generally affects the respiratory, gastrointestinal, and central nervous systems.  Canine distemper has the highest incidence of occurring in unvaccinated puppies, but can affect adult dogs, raccoons and ferrets.  

SOURCE & CAUSE(S)

As mentioned above, it is the Canine Distemper Virus (CDV) that is the cause of the disease.  Puppies between three and six months of age are most susceptible to infection and have the highest mortality rate.  Adult dogs who are not vaccinated can also be highly susceptible to contracting distemper.  The virus is spread through airborne transmission that is repertory droplets such as nasal discharge, coughing, and sneezing which can spread the disease over very short distances.  Due the nature of this virus, there is a much higher rate of contracting the disease in areas where there are high numbers of unvaccinated dogs.  This would include shelters, unregulated breeding operations, and even public parks where unvaccinated dogs have been. 

SIGNS & SYMPTOMS

Canine Distemper has a long list of signs and symptoms because the disease affects several systems of the body.  The following are organized by the stage of the disease that you will generally observe.

Early stage of infection

• Fever
• Loss of appetite
• Depression
• Mild eye inflammation that is usually short in duration

(All of these symptoms become more serious as the disease progresses.)

Secondary stage of infection

• Fever (This may or may not be present.  There are cases where fever peaks after the initial stage, then comes and goes)
• Discharge from the eyes
• Cough
• Nasal discharge (may be clear at first then progresses to yellow and green)
• Sneezing
• Vomiting
• Diarrhea

Advanced stages of disease

• Marked depression
• Stumbling or generally uncoordinated when walking
• Increased sensitivity to stimuli
• Various forms of paralysis
• Decreased motor function
• Mild to severe seizures (These seizures often effect different parts of the body.  Sometimes this can be described as tremors in the arms and legs or it will look like your dog is chewing gum if the seizure is affecting the head.  This is a seizure unique to a distemper patient.)

It is important to note that when distemper dogs began to show central nervous system symptoms, the disease is progressing into a dangerous state.  When a dog dies from distemper, most commonly they usually succumb to the various nervous system complications that develop.  If a distemper dog makes it through the disease, they will almost always have some pronounced chronic nervous system deficits. 

DIAGNOSIS & TESTS

Diagnosis for distemper is not an easy task; however, the basis for making a definitive diagnosis is based on clinical signs and most importantly the vaccine history of your puppy or adult dog.  There are several diagnostic tests that can be useful in diagnosing the secondary conditions that your pet might be exhibiting such as pneumonia, eye infections, or gastrointestinal problems.  However, there is really not one diagnostic test that can be done to give a sure positive for distemper.  Your veterinarian will rely heavily on a complete verbal medical history and description of signs and symptoms from you, as well as a complete history describing vaccination information and environment that your dog or puppy has been exposed to since symptoms became present.

TREATMENT & MANAGEMENT

There is no cure for distemper; therefore treatment consists of providing support therapy to address the symptoms that are being exhibited.  Your veterinarian will most likely admit your pet to the hospital under isolated conditions and provide the following:

• Administer anti-nausea and anti-vomiting drugs.

• Administer anti-diarrhea drugs.

• Administer i.v. fluids to help control dehydration.

• Administer anti-convulsants to help control seizures.

• Administer antibiotics and possible steroids to treat pneumonia and other respiratory symptoms.

• Provide an extensive amount of nursing care to keep your pet comfortable through the disease process.

The prognosis will depend on your dog’s immune response to all of the treatment.  In most cases, when your dog is admitted to the hospital, the prognosis is guarded at best.  Fifty percent of infected dogs usually succumb to the disease between two weeks and two months of initial infection. 

PREVENTION & HELPFUL TIPS

The good news about distemper is that it is a preventable disease.  The best prevention is vaccination.  It has been shown that dogs that have been exposed to the virus prior to vaccination have not contracted the disease.  This holds true if the dog is vaccinated within a week of exposure.  It is highly recommended that owners follow the vaccination schedule provided by your veterinarian.

• Puppies are born with antibodies from their mother that help fight of infections. These antibodies begin to weaken between the ages of 6 and 12 weeks.  This is when puppies should begin their vaccine schedule.   

• If there is a distemper dog in the house, this dog should be immediately isolated from other dogs in the family. 

• If there has been a distemper dog in the house, you should wait 2-3 months before introducing another dog into the house.