GRAND RAPIDS, Mich. (WOOD) — The latest data from the Michigan Department of Natural Resources shows that 25 deer tested positive for chronic wasting disease in 2021.

The DNR said a little over 7,200 deer were tested last year: a low number for pre-pandemic standards but triple the number of tests run in 2020. In that year, the agency recorded 20 deer with CWD. But the department warns comparing year-to-year data loses a lot of context due to its testing strategy.

“Some years we’ve intensified surveillance in known hot spots, and other years (including 2021) we have looked elsewhere trying to find the disease, specifically avoiding those hot spots,” Chad Stewart, a DNR deer, elk and moose management specialist, told News 8. “With that, it’s not really possible to compare the numbers between years at face value.”

Of the 25 CWD-positive deer, three cases of chronic wasting disease were detected in Isabella County, the first cases were found there.

Michigan’s first confirmed case of CWD was found in 2015 and has since been found in Clinton, Dickinson, Eaton, Gratiot, Ingham, Jackson, Kent and Montcalm counties, with Montcalm County, northeast Kent County and southern Jackson County showing the highest concentration of cases.

CWD testing peaked in 2018 and 2019, with a combined 50,000 deer tested and 127 positive tests. Stewart warned that hunters shouldn’t dismiss CWD as a threat despite the lower numbers.

“The distribution of our samples greatly affects the number of positives we expect to find. Intensive collection of samples in known CWD locations like Montcalm and Kent counties would certainly lead to a high number of positives being detected,” Stewart said in a news release. “Our goal this year was to begin to understand what CWD looks like in areas that are historically under-sampled, and we made a lot of strides on that front.”

Stewart also warned that, as of now, there’s no easy way to eradicate the disease completely.

“Once it becomes established, it is unlikely that we can reverse course on the disease. Prevention and early detection remain our best options for CWD management,” Stewart said.