Dogs that are not fully vaccinated are at the most risk, Wineland noted, adding that effective vaccines are available.
Full vaccination protects the animals against severe illness, and cases should not cause dog owners to “drastically change” how they care for their pets or where they plan to travel, the statement said.
Routine canine vaccinations include those against parvovirus, the department added.
“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,” said Kim Dodd, the director of the veterinary diagnostic laboratory at Michigan State University.
The affected dogs in Otsego County have generally been under 2 years old or elderly, the county shelter said.
“We have not seen any dogs … die that are PROPERLY vaccinated,” the shelter’s Facebook post reads.
Canine parvovirus is spread by dog-to-dog contact and contact with contaminated feces and environments, the veterinary medical association says. It is not contagious to people or other types of animals, the state agriculture department said.
Survival rates for parvovirus “can approach 90%” with proper treatment, though when death happens, it usually occurs 48 to 72 hours after symptoms start, the association says.
CNN’s Amy Simonson contributed to this report.