So What is Circovirus and what Should Pet Owners Know About it? Deborah Shores, DVM

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In the past few weeks, the media has been all over a new virus that is infecting dogs. This virus is called Canine Circovirus. Right now, veterinarians are still learning more about it and its effect on canines. 

So what is Canine Circovirus and what should pet owners know about it? 

Circoviruses are small viruses that are common in pigs and birds. Although canine circovirus shares similarities to porcine circovirus, it is not the same virus. Porcine circovirus is the cause of ‘wasting syndrome’ which results in many fatalities in young pigs. Avian circovirus commonly affects the beak and feathers, causing diseases and infections, some deadly. 

Although the route of infection is still not entirely known, it is thought that canine circovirus is spread through direct contact with an infected dog or its vomit or diarrhea. Boarding kennels, daycare facilities, and dog parks are especially easy places for your dog to become infected. Viruses can also be spread from animal to animal from the use of equipment or human contact. 

Clinical signs include vomiting, severe hemorrhagic (bloody) diarrhea, lethargy, neurologic symptoms and lack of appetite. Vasculitis, or inflammation of the blood vessels, is also a symptom. Vasculitis can cause the skin to slough (peel off). (1) 

Although circovirus may be a contributing factor in the multiple deaths, it cannot be said that all of the infected animals have circovirus. In Ohio, three dogs were reportedly dying of a mysterious virus. Investigations are currently underway by The Ohio Department of Agriculture to determine if these deaths are the result of circovirus.(2)

Veterinarians are quick to stress that there are many other diseases that have similar symptoms. Just because your dog is showing symptoms of circovirus, there is no guarantee that it is only circovirus causing the sickness.  A PCR fecal test can provide identification and diagnosis of circovirus.(1,3)

There have also been dogs that have been tested positive for circovirus, yet were completely healthy and did not show any symptoms. 

We recommend you consult your veterinarian immediately if your dog shows any of these symptoms, especially if you live in Ohio, Michigan or other States or Provinces in the Great Lakes region.(2) 


(1)  Fiala, J. 2013, September 10. Veterinarians Skeptical Canine Circovirus Alone is Sickening Dogs. The VIN News Service. 

(2)  Forshey, T. 2013, September 6. Press Release: Ohio Agriculture Department Working to Identify Cause of Dog Illnesses. Ohio Department of Agriculture. Media Contact:  Erica Hawkins. 1-614-752-9817. 

(3)  Linlin, L. et al., 2013, April. Circovirus in Tissues of Dogs with Vasculitis and Hemorrhage. Emerg Infect Dis. 19(4): 534-41.

ABOUT Deborah Shores, DVM

Dr. Deborah Shores is a graduate of the Mississippi State University College of Veterinary Medicine. She has many years of experience working in animal hospitals and clinics from Virginia to South Carolina, treating mainly dogs and cats. She has a special interest in nutrition and holistic veterinary medicine and plans to pursue an acupuncture certificate at the Chi Institute in Florida. She has two cats and recently lost her 8 year-old Australian Shepard to liver cancer. 

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