Canine Parvovirus (also called parvo) is a very contagious and potentially fatal viral disease seen in dogs. Most commonly, parvovirus causes gastroenteritis, or inflammation of the stomach and intestines.
Canine parvovirus is contagious and can survive for several months (some experts say as long as 2 years) in the environment, and is also resistant to many disinfectants. Infection can occur directly through contact with infected dogs, but also through indirect contact with contaminated surfaces and objects. It is estimated that parvovirus is fatal in 16-48% of cases. Consult your vet as soon as possible if your dog shows signs of parvovirus.
Dogs of any age can get parvo, depending on their vaccination history, but some dogs are more susceptible than others:
- Puppies 6-20 weeks old are most susceptible (it takes some time for the vaccination series to become fully protective).
- Unvaccinated dogs.
Certain breeds are at an increased risk from parvovirus including Rottweilers, American Pit Bull Terriers, Doberman Pinschers, and German Shepherds. Dogs under stress or which have other intestinal infections (including worms) or other health problems may be at higher risk.
Signs and Symptoms of Parvovirus
If your dog has the following symptoms, consult your vet. If parvovirus is the cause, early treatment is essential. Common signs of parvovirus include:
- Diarrhea (may be bloody)
- Lethargy (no energy, laying around)
- Loss of appetite
Diagnosis of Parvovirus
A tentative diagnosis of parvovirus can be made based on the age, vaccination history, symptoms and physical exam. Confirmation of the diagnosis is through detection of the virus in a fecal sample via a quick test kit. Sometimes other tests such as blood tests are recommended.
Treatment of Parvovirus
Treatment depends on the severity of disease and is aimed at managing symptoms until the virus runs its course. Fluid therapy to combat dehydration is extremely important. Medications are sometimes used to reduce vomiting. Antibiotics may be used to fight secondary bacterial infections, and in very severe cases blood or plasma transfusions may be given. Hospitalization is usually required.
Vaccination is the best defense against parvovirus. Your vet will recommend a course of vaccinations suitable for your dog. In puppies the first vaccine is typically given at about 6-8 weeks of age, and repeated every 4 weeks until 16-20 weeks of age, with yearly vaccines thereafter.
Until puppies have had their last vaccination, it is prudent to be careful about their exposure to other dogs and places where dogs frequently defecate (e.g., dog parks) to avoid exposure as much as possible.
Because the virus survives for so long, if you have had a dog with parvovirus in your home, you should be careful about introducing a new puppy or unvaccinated dog for at least 6 months (possibly longer). Discuss the risks with your vet.
Home Care and Disinfection
A dog with parvovirus should be isolated from other dogs, especially puppies. An infected dog can shed the virus for 3 weeks or more after being ill (keep your dog at home during this time to avoid spreading the virus to other dogs). Parvovirus is resistant to many disinfectants. A solution of one part bleach to 30 parts water is effective, but can only be used on bleach-safe items. Other disinfectants that are labeled as effective against parvovirus can also be used and may be available through your vet. However, because the virus is difficult to completely eliminate (especially in the yard), it is important to follow your vet’s advice about bringing a new dog into the home even after careful disinfection.
Question: How do I clean up my home now that my dog has been diagnosed with Parvo?
Parvovirus: Disinfecting the Environment of Parvo
One of the most common questions and concerns about parvovirus is how long it lasts and how to disinfect the environment. This is especially important if a new puppy will be brought into a possibly contaminated area. Read this FAQ to learn about disinfecting against parvovirus.
Answer: Parvovirus may survive for several months under certain conditions:
Sunlight and low humidity (arid) conditions will inactivate the virus quicker than cool, moist, shady conditions.
Exactly how long the virus survives depends on many factors – temperature, humidity levels, sunlight, etc. It should be noted that freezing temperatures are protective for this virus; cold temperatures won’t kill parvo.
Disinfecting the Environment of Parvo
NOTE: This section of the article is about environmental treatment for parvo. If you suspect that your dog or puppy has or has been exposed to parvo, please see your veterinarian as soon as possible. Time is of the essence for improving chances of survival.
Parvo is considered to be ubiquitous – it is potentially everywhere in the environment. The key is to minimize the amount of available virus and protect your dog through vaccination; activating the immune system to fight off the virus before it causes disease. Puppies younger than 16-18 weeks of age haven’t had all of their vaccinations yet, so they are more susceptible to parvovirus. Therefore special caution is advised for puppies; be mindful of the areas visited, vaccination status and age of dogs they come in contact with, and be extra vigilant about sanitation of hands, shoes, clothes, bowls, etc.
The mainstay for parvo disinfection for the environment is to use a diluted bleach solution on cleanable surfaces (never on an animal!). The type of bleach varies the “strength,” but a general rule of thumb is: 1 part bleach : 30 parts water. Learn more about the types of bleach, handling instructions and dilution factors: The Bleach Niche.
Washable surfaces may be cleaned with a dilute bleach solution (test small area of the item first). Washing with large amounts of water may help ‘dilute’ the virus from areas such as lawns. For furniture, carpets and other difficult-to-disinfect areas in the home, waiting 4-6 weeks should be sufficient time for the virus to die off before introducing another puppy. This virus is not transmissible to people, but people can transmit it to other dogs. So be certain to wash your hands thoroughly and often.