Dozens of dogs in Michigan have reportedly been sickened and killed by a parvovirus-like illness, local animal shelters said. 

The outbreak has been reported in northern and central Michigan. Canine parvovirus is a highly infectious disease that primarily impacts elderly canines and dogs under the age of 2. 

The illness spreads through fecal matter. Symptoms include tiredness, loss of appetite and diarrhea.

Melissa FitzGerald, Otsego County's animal control and shelter director, told FOX 17 Michigan that more than 30 dogs have passed away from an unidentified illness that appears to be similar to parvovirus.

LOUISIANA MOTHER AND DAUGHTER CHARGED WITH ANIMAL CRUELTY AFTER DOG TRAINING VIDEO SURFACES ONLINE

Strangely, all the dogs who died tested negative for parvovirus, despite showing the symptoms of disease.

The Michigan Department of Agriculture and Rural Development and Michigan State University Veterinary Diagnostic Laboratory are both conducting tests to understand the outbreak.

DOG INFECTED WITH MONKEYPOX AFTER SHARING BED, LICKING OWNERS

"What exactly is it, a strain of Parvo? Is it something else? Is it combined? There’s a lot of unanswered questions that they’re looking into at this point," FitzGerald said.

In the meantime, Michigan dog-owners are encouraged to properly vaccinate their dogs. 

"Make sure they’re up to date on all their vaccinations, make sure they were properly vaccinated when you got them whether it was when they were puppies or when they were three," FitzGerald recommended. "Keep your dogs close. Don’t let them sniff about – No common water dishes, anything like that."