Canine Parvovirus: A Deadly but Preventable Illness

canine parvovirus puppy

canine parvovirus parvo calgary humane society

By Caitlin Flegel, RVT

The Calgary Humane Society closed its doors on April 25th, 2017 (and reopened May 1st) because of a confirmed case of Canine Parvovirus in two puppies that were surrendered to them. Due to the potential for an outbreak, the Humane Society said it has closed the shelter as a precaution due to the positive Parvo test result and are “taking all necessary precautions” including quarantine and disinfecting the shelter to protect their animals and prevent the virus from spreading.

This incident has many of our clients wondering if they need to be concerned about Parvovirus, more commonly known as Parvo, and how they can protect their pets. We’ve put together some basic information about Canine Parvovirus, including the symptoms and how you can protect your pet against this potentially deadly disease.

Canine Parvovirus

First discovered in the 1970’s, Canine parvovirus (CPV) is a highly contagious and extremely deadly viral disease affecting dogs and young puppies. Characterized by severe bloody diarrhea, vomiting, anorexia, lethargy, and sudden marked weight loss, when left untreated, CPV has mortality rates as high as 91%. Young, unvaccinated puppies make up the majority of Parvo cases as the disease preys upon their immature and weakened immune systems.

Understanding CPV and its symptoms

Parvo manifests in two forms, intestinal and cardiac. The cardiac form is the lesser known of the two forms and generally only affects very young puppies infected in utero by their mother. This form attacks developing heart muscles and sadly, almost all puppies with the cardiac form of Parvo die.

The more common intestinal form blocks the body’s ability to absorb nutrients and water from the intestines and quickly leads to dehydration and diarrhea. While symptoms can vary from patient to patient, the most common signs are extreme lethargy (very low energy), severe bloody diarrhea, fever, anorexia, and vomiting.

Transmission of Canine Parvovirus

The intestinal form of Parvo is contracted through oral ingestion of the virus, which is transmitted through feces or feces-contaminated objects like water/food bowls, kennels, blankets, etc. Canine Parvovirus is incredibly hardy in the environment and can live upwards of 1 year in feces or other organic material! The only household disinfectant capable of destroying the virus is bleach.

Diagnosis and Treatment

Parvovirus is diagnosed via clinical signs and through lab analysis of a suspected patient’s feces. Early, aggressive treatment is critical to a positive outcome. CPV patients are treated in a veterinary hospital with IV fluids to combat severe dehydration, anti-nausea medications to curb vomiting, and strong IV antibiotics to prevent a secondary bacterial infection from occurring. Once the acute phase of infection has passed, the patient is slowly reintroduced to food and may continue to receive oral antibiotics until their immune system has fully recovered.


Fortunately, CPV can be prevented by following these 7 guidelines:

  1. Ensure your dog is fully vaccinated! Puppies should receive their first vaccine at 6-8 weeks of age and boosters should be given every 4 weeks for a total of 3 vaccines.
  2. Keep young, unvaccinated puppies away from other dogs and their feces. This includes your local dog parks, kennels, groomers, and anywhere else they could come into contact with another dog’s feces.
  3. Carry your puppy in your arms outside your local vet clinic and in the lobby.
  4. If purchasing a puppy from a breeder, ensure the mother is fully vaccinated to prevent in-utero transmission of the virus.
  5. Call your veterinarian immediately if you suspect your dog or puppy has CPV or shows any of the following symptoms: severe bloody diarrhea, lethargy, vomiting, or fever.
To learn more about the in-home veterinary services we provide, including in-home parvo vaccinations, in the Calgary and Edmonton area, please give us a call at 1-888-995-8387 or request our welcome kit online.

Leave a Reply