Jan 2013 - Message on Canine Circovirus from DCPAH and MDARD

The following is a 10/3/2013 MVMA Message on Canine Circovirus from DCPAH and MDARD:

Based on recent cases in California and Ohio that may indicate the emergence of a new canine circovirus, the Diagnostic Center for Population and Animal Health (DCPAH) at the Michigan State University College of Veterinary Medicine has added two real time PCR assays for canine circovirus to its test catalog. Running two PCRs for this virus is important as the initial research on the virus indicates some genetic variation. The PCR assay can be run on fresh or formalin-fixed tissue. DCPAH has received requests for canine circovirus testing from Michigan clients and two positive results have been found. However, both animals also had simultaneous infections with other organisms; therefore identification of the circovirus was not necessarily linked to the cause of the disease shown by the animals. DCPAH is currently working on an in situ hybridization (ISH) technique which is a crucial next step. ISH is a method that uses DNA or RNA probes to detect virus in microscopic lesions.

"It is important to note that circovirus has been found in the feces of healthy dogs. Also, the initial research shows that nearly 70% of dogs showing clinical signs of illness and found positive for circovirus were also infected with other viruses or bacteria known to cause disease. Currently, circovirus by itself is not associated with a specific disease process. However, coinfection with canine circovirus and other pathogens may have the potential to cause disease as has been demonstrated in other species, for example pigs," says DCPAH acting director Thomas Mullaney.

Matti Kiupel, section chief for DCPAH's pathology laboratory adds, "In order to link circovirus to the cause of a disease process, a full diagnostic work-up (including a postmortem in the case of deceased animals) is essential. This also allows diagnosticians and pathologists to identify the full spectrum of infections and/or diseases that are present in a specific case."

Recent publicity about circovirus in Michigan dogs is not cause for panic. Veterinarians should consider possible circovirus infection in animals showing clinical signs including vomiting, diarrhea (possibly hemorrhagic) only after other more common causes have been diagnostically excluded. Ascites, pleural effusion, hypovolemic shock, bicavitary hemorrhage, and disseminated intravascular coagulation may also be present, but as with gastrointestinal symptoms, more common causes should be excluded. According to the early research by Li et al, circovirus "should be considered in cases of unexplained vasculitis in dogs." Please contact DCPAH at (517)353-1683 for more information on submitting samples for testing.

Dog owners whose pets show signs of illness, including vomiting, diarrhea, lethargy, should contact their veterinarian and seek diagnosis and treatment. There is no evidence to-date that canine circovirus can be transmitted to humans or cause human disease. Since many pathogens are transmitted from animals to humans (zoonotic diseases such as rabies, leptospirosis, salmonellosis) thorough hand-washing should be standard practice after handling animals, especially those showing signs of illness, or animal waste.

Additional information on circovirus developed by the American Veterinary Medical Association (AVMA) for veterinarians and the general public is available on their website

View the Original Statement from DCPAH Here

Talking Points on Canine Circovirus from MDARD


  • Circoviruses are small viruses that have been known to infect pigs and birds. They are also known to survive well in the environment once shed from affected animals. In April of 2013, the University of California, Davis discovered a new strain of circovirus in dogs.
  • It is important to note that canine circovirus is newly isolated and there is very little information available about the virus, where it came from and how it spreads. The limited research available shows that canine circovirus can cause vasculitis and hemorrhaging in infected dogs which can cause vomiting, bloody diarrhea, lethargy, and weight loss.
  • While there were suspect cases of cirovirus in Ohio, the Ohio Department of Agriculture is no longer considering canine circovirus as a primary culprit in their investigation. Ongoing sample analysis is searching for new or different viral agents that could be the causes of these illnesses.

Current Situation

  • The Michigan Department of Agriculture and Rural Development (MDARD) has been following up on reported cases of ill dogs displaying vomiting, bloody diarrhea, and lethargy to which other diseases were ruled out to see if circovirus is present.
  • Circovirus is not a reportable disease in Michigan; however, MDARD veterinarians have been working in close partnership with Michigan State University's Diagnostic Center for Population and Animal Health (MSU DCPAH), the Michigan Veterinary Medical Association, local animal control officers, and private veterinary practioners as we are concerned about the possible presence of this virus in Michigan.
  • Since a suspect case was identified in Ohio, MDARD has been working to educate animal control officers and veterinarians regarding this virus, including signs and symptoms.
  • We are still in the very early investigative stages, and MDARD is not prepared at this time to confirm canine circovirus as the cause of the dog illnesses. Additional analysis and information is needed to determine if this virus alone or in co-infection contributes to illness and death in dogs.
  • MSU's DCPAH is offering circovirus testing in response to concerns about this virus. MDARD is recommending veterinarians contact MSU DCPAH for consultation if they suspect they are treating a related case.
  • This is not known to be a zoonotic disease.
  • Pet owners are encouraged to follow normal, common sense preventative veterinary medical practices such as vaccinations and regular veterinary care.

View the Original Statement from MDARD Here