Parvovirus is a highly contagious viral disease that causes severe gastrointestinal (GI) signs in dogs and puppies. Without prompt treatment, parvovirus is often fatal, but with aggressive therapy and supportive care, survival rates are 85% to 95%. Our Desert Vet team wants to provide information about this dangerous disease to help protect your four-legged friend.

What is parvovirus in dogs?

Parvoviruses are prevalent, and almost every mammalian species has their own parvovirus specific to their species. The original canine parvovirus (CPV-1) that was discovered in 1967 represented a medical threat only to newborn puppies. Then, a new variant (CPV-2) emerged in Europe in 1976 and spread to the United States by 1978. Infected dogs shed the virus in extremely large numbers, and the virus, which is especially hardy in the environment, was rapidly distributed worldwide. Parvovirus is similar to the feline panleukopenia virus and attacks rapidly dividing host cells, such as intestinal cells, bone marrow cells, lymph system cells, and fetal cells. More than 40 years later, the disease remains a significant problem for puppies and unvaccinated dogs. 

How is parvovirus spread in dogs?

The virus is shed in an infective dog’s feces, from shortly before clinical signs develop until about 14 days after clinical signs resolve. Susceptible dogs and puppies become infected when they ingest the virus, which is easily transmitted on any object, including hands, shoes, and food and water bowls, contaminated with an infected dog’s feces. Once infection occurs, the virus targets rapidly dividing cells and attacks the bone marrow, weakening the body’s ability to mount an immune response by decreasing the white blood cell (WBC) count. This makes invading the intestine easier, and the virus attacks the intestinal wall, causing severe inflammation and damage, and leaving the intestinal surface unable to adequately absorb nutrients, retain fluid properly, or prevent bacteria from moving from the GI tract into the body, leading to widespread infection. In puppies, the virus can also infect the heart, causing heart muscle inflammation and arrhythmias and leading to heart failure.

How is parvovirus diagnosed in dogs?

Puppies younger than 5 months and unvaccinated dogs are at highest risk for parvovirus. Clinical signs, which typically develop about 6 to 10 days after exposure, include fever, depression, inappetence, severe vomiting, and diarrhea that may contain mucous or blood. Parvovirus should be suspected in any puppy or unvaccinated dog who exhibits these signs. Potential diagnostic tools include:

  • Complete blood count (CBC) — A tentative diagnosis is often made based on a reduced WBC count and indicative clinical signs.
  • Stool test — For confirmation, our veterinary team may test your dog’s stool for the virus.
  • Blood test — We may also test your dog’s serum for anti-parvovirus antibodies.

How is parvovirus treated in dogs?

No medication can kill the virus, so treatment focuses on supportive care to help the dog’s immune system fight off the infection. Treatment strategies include:

  • Isolation — Infected dogs and puppies are isolated to minimize infection spread.
  • Hospitalization — Hospitalization is often necessary to provide your dog with appropriate intensive care.
  • Fluid therapy — Our veterinary team typically administers intravenous fluids to replace fluid and electrolyte losses from diarrhea and vomiting. 
  • Medications — We may recommend medications, such as anti-emetics and anti-spasmodics, to help control your dog’s vomiting and diarrhea.
  • Antibiotics — Antibiotics may be necessary to control infection if bacteria enter the bloodstream from the GI tract.
  • Nutritional support — In prolonged cases, our veterinary team may implement parenteral nutrition to meet your dog’s nutritional needs.

How is parvovirus prevented in dogs?

The best parvovirus protection for your dog is ensuring they are properly vaccinated. Puppies should receive their first parvovirus vaccine at about 6 weeks of age and booster shots every three to four weeks until they are about 16 weeks of age. Our veterinary team recommends a booster one year after their final puppy shot, and then every one to three years, depending on their lifestyle. Other ways to help prevent parvovirus include:

  • Good hygiene — Promptly and properly dispose of all fecal waste to limit infection spread, and don’t let your dog contact other dogs’ fecal waste.
  • Limit exposure — Until your puppy has received their complete vaccine series, avoid dog parks, doggy daycare facilities, and grooming establishments, where they could potentially contact unvaccinated dogs. 

Parvovirus is a concerning disease that can cause significant health complications for your dog, but you can protect them from this dangerous illness by ensuring their vaccinations are kept up to date. If your dog is due for their parvovirus vaccination, contact our Desert Vet team, so we can ensure they are properly protected.