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FAQs About Parvovirus in Dogs

By February 11, 2022September 20th, 2023No Comments

If you are a dog owner, you likely have been warned about parvovirus, a highly contagious, dangerous, and sometimes fatal disease that can cause severe gastrointestinal problems for dogs and puppies. Our team at Animal Emergency Hospital and Urgent Care wants to help by answering some frequently asked questions about parvovirus, so you know how to protect your pet.

Question: What causes parvovirus in dogs?

Answer: The canine parvovirus (CPV) type 2 causes parvo in dogs. The virus was first observed in Europe around 1976, and the disease had spread worldwide and caused an epidemic by 1978. CPV probably was the result of genetic mutations in the feline panleukopenia virus (FPV), which has caused infection in cats and minks since the 1920s. CPV also affects other animals, including coyotes, wolves, foxes, raccoons, and skunks.

Q: How do dogs get parvovirus?

A: Parvovirus is transmitted by exposure to infected fecal matter or contaminated surfaces. The virus can live on kennel surfaces, on people’s hands and clothing, and in the soil at dog parks. While all dogs can be infected, unvaccinated dogs and puppies 6 weeks to 6 months of age are at higher risk.

Q: How does parvovirus progress in dogs?

A: When a dog or puppy becomes infected with parvovirus, a three- to seven-day incubation period occurs before they exhibit signs. During this time, the virus attacks the tonsils and lymph nodes of the throat, to invade lymphocytes, to replicate themselves. The virus then uses the lymphocytes to access the bloodstream, where they target rapidly dividing cells, such as those in the bone marrow and the gastrointestinal (GI) tract. During this process, many lymphocytes are killed, leaving a reduced number of circulating lymphocytes, which are a white blood cell type that typically helps combat infection.

  • What happens in the bone marrow? — The virus destroys young immune cells, decreasing the body’s ability to fight infection. This allows the virus to easily access the GI tract, where the worst damage is done.
  • What happens in the gastrointestinal tract? — The small intestinal lining normally absorbs nutrients, and provides an important barrier to help prevent fluid loss and bacteria spread from the gut into the body. The cells that compose this lining are replaced continually by new cells born in an area called the crypts of Lieberkuhn. CPV attacks these crypts, preventing the body from making new cells to replace the intestinal lining. Without an adequate intestinal lining, the body can’t absorb nutrients, prevent fluid loss, or prevent bacterial invasion from the gut into the body.
  • What happens in the heart? — In puppies, CPV can attack the heart, causing inflammation, and blood cannot be pumped effectively through the body.

Q: What are parvovirus signs in dogs?

A: Dogs and puppies affected by parvovirus are typically seriously ill, and the sooner these pets receive veterinary attention, the better their prognosis. Initially, signs include lethargy, decreased appetite, and a fever, and severe vomiting and diarrhea as the disease progresses. Puppies whose heart is affected by the virus may collapse.

Q: How is parvovirus diagnosed in dogs?

A: Parvovirus is diagnosed based on clinical signs and blood work. Since the virus attacks the bone marrow, dogs infected by parvovirus typically have an extremely low white blood cell count that suggests CPV infection, especially if they are experiencing severe vomiting and diarrhea. In addition, our veterinary professionals may run a test on your dog’s feces to confirm the diagnosis.

Q: How is parvovirus treated in dogs?

A: Parvovirus has no cure, and treatment focuses on supportive care. Most affected dogs and puppies require a hospital stay to appropriately manage their condition.

  • Intravenous fluids — Fluid therapy is necessary, to replace the extensive fluid loss caused by the virus, and because oral fluids can’t be readily absorbed, since the GI lining is demolished.
  • Nutrition — Affected dogs and puppies will need adequate nutrients, which frequently are provided through intravenous administration, until their gut heals enough for them to accept food. They may then need a feeding tube until their appetite returns.
  • Antibiotics — If bacteria from the gut have entered the pet’s bloodstream, antibiotics may be needed, to counter these infections.
  • Blood transfusions — Blood or plasma transfusions may be necessary in severe cases, to boost white blood cell counts to help fight the infection.

Q: How is parvovirus prevented in dogs?

A: The best way to protect your puppy or dog from parvovirus is to vaccinate them appropriately at the recommended age, and to keep their vaccines up to date. The parvovirus vaccine is part of a combination vaccine given every three to four weeks from about 6 weeks until 16 weeks of age. In addition, ensure your puppy does not contact any dogs whose vaccination status is unknown, until they are fully vaccinated. When socializing your puppy, ensure they interact with fully vaccinated pets only, and they attend only puppy classes that require proof of vaccination for participants. You should also keep your pet away from fecal material, to protect them against CPV.

Parvovirus is an extremely dangerous disease, but you can take steps to keep your dog from being affected. If your dog is showing parvovirus signs, immediately contact our team at Animal Emergency Hospital and Urgent Care, so we can begin treatment as soon as possible.