UPDATE: Mystery Virus Killing Dogs in Michigan Confirmed to Be Parvo; Officials Encourage Vaccination

Earlier in the week, officials sounded an alarm about a parvo-like virus affecting elderly dogs and those under 2 around the state of Michigan

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Animal health officials in Michigan have solved a sad mystery plaguing the state's dogs: an illness that has killed more than 20 pups in recent weeks is in fact parvovirus.

According to a release from Michigan's Department of Agriculture & Rural Development, the dogs that died — who were mainly less than 2 years old or in their senior years — "did not have a history of complete vaccination." The parvovirus vaccine is considered a "core" inoculation for dogs, per the ASPCA.

Parvovirus is a highly contagious disease among canines, though it can't spread to humans. However, it can be severe, especially for animals who aren't fully vaccinated.

On Aug. 19, the Otsego County Animal Shelter shared on its Facebook page that a mystery virus, presenting much like parvovirus, had killed nearly two-dozen dogs in Ostego County. The animals who were brought to veterinarians after developing the stomach-related symptoms of the illness were testing negative for parvo.

In the release from the Department of Agriculture & Rural Development, Michigan State University Veterinary Diagnostic Laboratory director Dr. Kim Dodd said that further testing was in fact showing the deceased dogs all had parvo. "While those tests are valuable in the clinical setting, they are not as sensitive as the diagnostic tests we can perform here in the laboratory," she shared. "We continue to further characterize the virus in hopes of better understanding why those animals were testing negative on screening tests."

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Due to the false negatives, Dr. Dodd and her team are encouraging vets who see sick dogs testing negative for parvo to pursue additional labwork through the MSU VDL. Additionally, animal owners should keep their dogs home if they are showing any symptoms of parvo — lethargy, fever or chills, vomiting, bloating and diarrhea among them — and clean up after their animals properly on walks.

"Dog owners across Michigan must work closely with their veterinarians to ensure their dogs are appropriately vaccinated and given timely boosters to keep their pets safe and healthy," reads the Department of Agriculture & Rural Development release. "Protecting Michigan's dogs is a team effort."