GRAND RAPIDS, Mich. (WOOD) — An illness affecting dogs in the northern Lower Peninsula is canine parvovirus, state officials say.

The dogs who became sick were not fully vaccinated, the Michigan Department of Agriculture and Rural Development said in a release. Sixty dogs have died, a number that has doubled in just a matter of days.

“This situation is complex because although the dogs displayed clinical signs suggestive of parvovirus, they consistently test negative by point-of-care tests performed in clinics and shelters,” said Michigan State University Veterinary Diagnostic Laboratory director Kim Dodd, DVM, said in the release. “Screening tests for parvo are done to help guide immediate isolation, disinfection, and treatment protocols. 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. We continue to further characterize the virus in hopes of better understanding why those animals were testing negative on screening tests.”

Canine parvovirus is highly contagious, MDARD said. To protect your pet, make sure your dog is fully vaccinated and do not let it interact with other dogs before then.

“We have a highly effective vaccine available to help protect dogs from the virus. Dogs that are not fully vaccinated against this virus are the most at risk,” state veterinarian Nora Wineland, DVM, said in the release. “Protecting Michigan’s dogs is a team effort.” 

Clean up after your pet in public. If your dog starts showing symptoms, keep it away from other animals and contact your veterinarian. Symptoms can include vomiting, diarrhea and blood in stool.

Canine parvovirus is not contagious to people or other domestic animals.

More information about canine parvovirus can be found at avma.org.