Canine parvovirus infection in dogs is a viral disease that affects puppies and un-vaccinated adult dogs. It can be fatal. The virus is resistant to may common disinfectants and can survive in contaminated areas for several months. Doberman Pinschers, German Shepherds, Rottweilers and American Pit Bull Terriers are at an increased risk of the disease. The death rate of canine parvovirus is reported to be between sixteen to forty eight per cent.
Canine parvovirus is contacted through direct contact with infected dogs, or indirect contact, such as objects that have been contaminated by the fecal matter of infected dogs. The virus can remain in the feces for three weeks after infection. Dogs who have recovered from the infection can serve as carriers. After the virus is ingested, it reproduces and spreads into the bloodstream. It then attacks the cells throughout the body, particularly blood cell producing tissue. bone marrow and the lining in the small intestine. It does this very quickly. When is is in the intestinal lining, it can cause bloody diarrhea and severe damage. The bacteria which is normally present in the intestines can enter the tissue and bloodstream through the damaged areas which can worsen the disease.
There may not be any symptoms of illness and an infected dog may be contagious before any symptoms appear. It can be triggered by stress, for example from boarding kennels. Symptoms can be worsened by other digestive system infections. The risk of infection is increased if a non-infected dog has prolonged contact with an animal who is shedding high levels of the virus.
Over eighty five per cent of infected dogs are under a year old. It is common for pups between six and twenty weeks to suffer from gastroenteritis, which is inflammation of the stomach and intestines. The level of antibodies gained from the mother during nursing is declining at this time and the vaccinations may not be providing adequate protection against infection.
It is possible for symptoms of the intestinal form to include fever, vomiting, appetite loss, diarrhea and sudden lethargy. The feces are loose and blood or mucus may be present. The severity of the symptoms is variable. Some dogs can die within a few hours of the appearance of symptoms, and others can recover with appropriate supportive care. Diagnosis is confirmed with fecal or blood tests and is based on a detailed history of the dog. The fecal test can give a negative result of viral protein if it is performed early in the disease course. It may need to be repeated if all indications are of canine parvovirus.
Treatment and Control
While there is no specific treatment of elimination of the virus, most dogs recover with supportive care focused on fluid replacement. Oral electrolyte solutions can be used in dogs who are mildly dehydrated and have not been vomiting. The solutions will replace the potassium and sodium that is lost through the intestines. Dogs that are more severely affected will need intravenous fluids. Animals that survive the first two to three days of disease will generally recover. If there is persistent vomiting, the veterinarian may prescribe medication to control it. Antibiotics will be prescribed if there is a risk of a secondary bacterial infection. The owner should careful follow instructions from the veterinarian regarding the diet. Food and water should be withheld until the vomiting has stopped. Once vomiting has subsided, the animal can be given small frequent meals of a bland diet. This can include rice, cottage cheese or may be a prescription diet. The owner should contact the veterinarian if symptoms recur. Food may need to be withheld for another twelve to twenty four hours. If the food is tolerated, the animal should continue with the bland diet for one or two weeks. After this, the normal diet can be reintroduced gradually.
Any contaminated areas should be cleaned thoroughly and disinfected. There are commercial products available that are labeled for use against parvovirus. Household bleach diluted to one part bleach to thirty parts water will also work. The solution can be used as a foot bath to disinfect footwear. It is recommend to disinfect food and water bowls, clothing, toys and hands. Puppies should be isolated from any adult dogs who have left the home to go to shows or trials. The critical element of controlling parvovirus is vaccination. Puppies begin the vaccinations between five and eight weeks old. The final vaccination is given between sixteen and twenty weeks. The animal should then have another vaccination once a year. The veterinarian will recommend vaccinations to protect the dog.