Canine distemper occurs wherever there are dogs. It is the greatest single disease threat to the world's dog population.

Better than 50% of the adult dogs that contract the disease die from it. Among puppies, the death rate from distemper often reaches 80%.

Even if a dog does not die from the disease, its health may be permanently impaired. About with canine distemper can leave a dog's nervous system irreparably damaged, along with its sense of smell, hearing or sight. Partial or total paralysis is not uncommon, and other diseases--particularly pneumonia--frequently strike dogs already weakened by a distemper infection.

Younger dogs and puppies are the most susceptible to infection. The disease also strikes older dogs, although much less frequently.

Cats are not susceptible to canine distemper. The so-called "cat distemper" is a different disease caused by a different virus. Infectious canine hepatitis is a separate disease but may occur simultaneously with canine distemper. Neither distemper nor infectious canine hepatitis is transmissible to man.

Canine distemper is a highly contagious disease caused by a tiny virus.

Canine distemper virus is most often transmitted through contact with mucous and watery secretions discharged from eyes and noses of infected dogs. Contact with the urine and fecal material of infected dogs can also result in infection. A healthy dog can be infected without coming in contact with an infected animal. Kennels, runs and other areas used by infected dogs can harbor canine distemper virus. The virus may be borne by air currents and inanimate objects. Short of raising a dog in total isolation, it is nearly impossible to prevent exposure. Some veterinary medical scientists estimate that practically every dog that lives to be a year old has had contact with the virus at some time.

The many signs of distemper are not always typical. For this reason, treatment may be delayed or neglected. The disease frequently brings about something like a severe cold. Most infected dogs have a fever and "stuffed up" head. Exposed animals may develop bronchitis, pneumonia and severe inflammation of the stomach and intestines.

The first signs of distemper an owner might notice are squinting, congestion of the eyes, and a discharge of pus from the eyes. Weight loss, coughing, vomiting, nasal discharge, and diarrhea are common. In later stages the virus frequently attacks the nervous system, bringing about partial or complete paralysis as well as "fits" or twitching. Dogs suffering from the disease are usually listless and have poor appetites.

Sometimes the signs may be very mild and perhaps go unrecognized, or the dog may have a slight fever for a couple of weeks. If pneumonia, intestinal inflammation or other problems develop, recovery takes much longer. Nervous problems often last many weeks after the animal has recovered from all other signs of infection. Occasionally the virus causes rapid growth of the tough keratin cells on the footpad, resulting in a hardened pad.

Distemper is so prevalent and the signs so varied that any sick young dog should be taken to a veterinarian for a definite diagnosis.

Dogs that survive a natural infection usually develop sufficient immunity to protect them from distemper the rest of their lives. Many dogs--particularly pups--do not survive a naturally-acquired infection. The safest protection is vaccination, but unfortunately, scientists have not yet developed a distemper vaccine which will guarantee lifetime immunity with a single series of inoculations. Therefore, most veterinarians recommend annual vaccinations for your dog.

Puppies born to dogs which are immune to distemper acquire a degree of natural immunity from nursing. This immunity is acquired through substances in the colostral milk produced by the mother the first few days after giving birth. The degree of protection a pup receives varies in proportion to the amount of antibody its mother has, but it is never complete. This passive immunity transferred from the mother also diminishes rapidly. The pup loses about half of it by the time it is 8 days old and nearly three-fourths by the time it is 2 weeks old.

Veterinary medical scientists have developed effective means of predicting the critical time when a pup loses the immunity transferred from its mother and becomes receptive to vaccine immunization. Using blood samples taken from the mother before she whelps, a veterinarian can detrmine when a pup will become susceptible to distemper infection. Check with your veterinarian to determine your dog's immune status.

It is impossible for a pet owner to determine when a dog should be vaccinated because of the variations from animal to animal. Your veterinarian can determine the most advantageous time to begin vaccination based upon his or her experience and the general health of your dog.