WHAT DOG OWNERS SHOULD KNOW ABOUT PARVO AMID OUTBREAK IN ONTARIO CITY

Recent outbreaks of canine parvovirus (CPV) in Ontario have triggered a surge in online searches about the disease.

When asked about the outbreak earlier this summer in London and the overall presence of CPV in Canada, veterinary expert Dr. Tracy Fisher said the virus remains a common and persistent concern.

Fisher, a Regina-based veterinarian and president-elect of the Canadian Veterinary Medical Association, told CTVNews.ca that the number of cases can vary from year to year.

How do dogs get parvo?

Canine parvovirus (CPV), also known as parvo, was first detected in dogs in 1978, according to VCA Canada, the Canadian division of the Veterinary Centers of America.

The virus is closely related to feline panleukopenia (feline distemper), and while the two diseases appear nearly identical, VCA Canada notes that this connection has not been scientifically confirmed.

Parvo is highly contagious and is primarily spread when a dog ingests feces from an infected animal. However, it can also be transmitted through indirect contact—such as on the hair, feet, or belongings of infected dogs, or surfaces contaminated by feces.

Once inside the body, the virus targets the tonsils and lymph nodes, where it attacks lymphocytes (white blood cells). These cells then carry the virus to other parts of the body, including the bone marrow and intestinal lining, causing widespread illness.

Animal shelters are especially vulnerable to outbreaks due to the close quarters and the presence of unvaccinated dogs, making rapid transmission more likely.

Parvo symptoms

The main symptoms of canine parvovirus (CPV) include severe vomiting and diarrhea, often with a strong odour and containing mucus and blood. Infected dogs may also experience loss of appetite, fever, and depression, according to VCA Canada.

CPV is most common in unvaccinated dogs under one year of age.

While the disease is generally not fatal, certain breeds—such as Rottweilers, Doberman Pinschers, Labrador Retrievers, American Staffordshire Terriers, and Arctic sled dogs—have a higher risk of death, according to veterinary experts.

Dr. Tracy Fisher notes that the severity of the disease and chances of survival also depend on the dog’s age.

“Very young puppies almost never survive without supportive care,” she said. “Their survival rates can be as low as 20 to 30 percent if left untreated.”

Parvo treatment

Unfortunately, there is currently no approved treatment for canine parvovirus (CPV) available in Canada, Dr. Tracy Fisher explained.

However, with hospitalization and intensive supportive care, survival rates can exceed 80 percent.

“The traditional approach involves very intensive supportive care,” Fisher said. “This includes intravenous fluids, managing nausea and blood sugar levels, and administering antibiotics to prevent secondary infections. It’s a demanding process.”

A new treatment, a monoclonal antibody therapy, has recently received conditional approval in the U.S. It shows promise for treating puppies and dogs exposed to CPV, according to the veterinary publication dvm360.com.

While this treatment is not yet approved or available in Canada, Fisher considers the U.S. approval a hopeful development.

“This therapy provides animals with antibodies specifically targeting the parvovirus,” she said. “We’re very excited about its potential because parvo is such a devastating disease.”

She also noted that improvements in vaccines over time have played a crucial role in controlling the spread of parvo.

How common is parvo in Canada?

Dr. Fisher said she typically treats about two to three parvo cases a year at her Regina practice, noting that outbreaks tend to be localized to specific areas.

In late June, a CPV outbreak in a London housing community prompted local veterinarians to set up a mobile clinic, offering low-cost testing and vaccinations for residents’ dogs.

Earlier, in December, an outbreak in Windsor resulted in the deaths of 14 dogs, according to CTV News.

Last fall, a Winnipeg dog rescue group also issued a warning about a potential CPV outbreak in parts of Manitoba.

Fisher emphasizes that prevention is the best defence against parvo. “Make sure your dogs, especially puppies, are vaccinated on schedule,” she advised.