Dogs that are not fully vaccinated are most at risk, Wineland noted, adding that effective vaccines are available.
Full vaccination protects the animals from serious illness, and cases should not cause dog owners to “drasically” change how they care for their pets or where they plan to travel, the statement said.
Routine vaccinations for dogs 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 lab. We continue to characterize the virus further in hopes of better understanding why those animals tested negative on screening tests,” said Kim Dodd, the director of the veterinary diagnostic laboratory at Michigan State University.
The affected dogs in Otsego County were generally younger than 2 years of age, the local shelter said.
“We haven’t seen any dogs die…that have been WELL vaccinated,” reads the shelter’s Facebook post.
Canine parvovirus is spread through dog-to-dog contact and contact with contaminated feces and environments, the Veterinary Medical Association says. It is not contagious to humans or other types of animals, the state agriculture ministry said.
Survival rates for parvovirus “can approach 90%” with proper treatment, but when death occurs, it usually occurs 48 to 72 hours after symptoms begin, the association says.
CNN’s Amy Simonson contributed to this report.