CANINE VIRAL DISEASES

The incidence of fatal diseases in dogs has luckily been drastically reduced over the last few years thanks to improvements in vaccines, quarantine laws and increased knowledge of what they actually are and consequently how they can be prevented. There are several serious diseases that may prove fatal in dogs but their risk of catching any of these can be greatly reduced by proper vaccination (with the exception of rabies, which is controlled in Australia, Britain and some other countries by strict quarantine regulations).

Canine Hepatitis
This virus is a highly contagious disease transmitted only to dogs and should not be confused with hepatitis in man. Primarily it affects the liver, kidneys and lining of the blood vessels.

Infectious canine hepatitis presents a variety of signs and symptoms that range from those of a mild infection to one of an extreme and rapidly fatal infection. At times it is difficult to distinguish from distemper. A few days after a dog is exposed, the virus multiplies in the dogs tissues and is shed through its stool, saliva and urine, which is extremely infectious to other dogs.

Convalescing dogs or those that have recovered may shed the virus through their urine for several months. Puppies are especially at risk although dogs of all ages are susceptible. In the fatal form affected dogs can suddenly become ill developing bloody diarrhea, collapsing and dying.

In mild cases the dog simply appears lethargic or below normal health and shows a lack of appetite. In acute cases the dog may run a fever reaching 106 degrees F. The dog passes bloody diarrhea, may vomit blood and will refuse to eat. Movement is painful and the dog can show a "tucked-up" belly, which is caused by a painful swelling of the liver. The eyes may be sensitive to light causing squinting.

Canine Distemper
A virus similar to the germ that causes measles in people causes this disease and world-wide it is the leading cause of infectious disease deaths in dogs.
The distemper can live for many years in a frozen state. During spring, the virus thaws out perhaps accounting for the higher incidence of distemper during spring months.

Distemper can attack virtually all the dog's body tissues and so has a wide range of symptoms. It is more common in younger animals but can occur at any age. The overall condition of the dog has a lot to do with how sick the dog gets and it is more severe in poorly nourished and ill-kept dogs. Although dogs can, and do, recover they seldom return to normal once the virus has reached the nervous system and brain.
The disease begins with a fever and loss of appetite, with a watery discharge from the eyes and nose, accompanied by coughing, vomiting and/or diarrhea and general lethargy. Fits, nervous twitching and finally paralysis can follow this. Distemper can also cause a hardening of the nose and pads, hence its original name hard pad.

Canine Parvovirus
This disease has a special affinity for attacking rapidly reproducing cells – such as those lining the intestinal tract, bone marrow, lymph nodes and heart. The virus, which is highly contagious, is transmitted from one dog to another via contaminated droplets and faeces.

It can be carried on the dog’s hair and feet, as well as on contaminated cages, shoes and other objects. Dogs of all ages are affected, but the highest mortality occurs among puppies less than five months of age.

Two main syndromes are recognized:
1. Diarrhea Syndrome (Enteritis)
After an incubation period of seven to fourteen days, the first signs are severe depression with loss of appetite, followed by vomiting. The dog appears to be in extreme pain, with a tucked-up abdomen.
Within 24 hours a high fever develops and profuse diarrhea that is frequently bloody. Almost no other disease produces such devastating symptoms.
2. Cardiac Syndrome (Myocarditis)
This form of Parvovirus affects the muscle of the heart, especially in puppies less than 3 months of age. Puppies with myocarditis stop nursing, cry out and gasp for breath. Death can occur suddenly or in a few days. Puppies that recover sometimes develop a chronic form of congestive heart failure that leads to death in weeks or months.

The quarters where an infected is or has been kept should be cleaned and thoroughly disinfected. This is an extremely hardy virus that resists most household cleaners. The best disinfectant is Clorox (one part to thirty parts of water).

Infectious Tracheobronchitis (Kennel Cough)
This is a highly contagious disease of dogs that spreads rapidly through a kennel. A harsh dry cough is the characteristic sign of the illness. The cough may persist for many weeks and become a chronic problem due to secondary infection.

A number of viruses have been implicated in the kennel cough complex. Two of these are immunized against through the normal yearly vaccination from your vet.