Weather Forecast


Record number of Lyme cases reported

Last winter’s heavy snowfall across Minnesota likely helped the survival of ticks that can carry disease, prompting state health officials today to urge precautions against tick bites.

Minnesota’s blacklegged ticks (also called deer ticks) were likely insulated from cold winter temperatures by deep snow in the wooded and brushy areas where the ticks are found, said David Neitzel, a tick-borne disease specialist with the Minnesota Department of Health.

“We are currently finding large numbers of the adult blacklegged ticks at central and southeastern Minnesota field study locations and expect the immature nymph stage of the tick to become active very soon.”

The highest risk for exposure to disease-carrying ticks is typically from mid-May through mid-July when these small and hard to detect nymphs are active.

“We expect that tick-transmitted disease risk will be high again this year, including in those places that are historically high risk,” Neitzel said.

Those areas include wooded or brushy habitats in southeastern, central and north central Minnesota.

In 2013, a record 1,431 Lyme disease cases were reported in Minnesota residents. In addition, cases of human anaplasmosis and babesiosis were also high at 627 and 64, respectively.

Besides these three commonly reported diseases, blacklegged ticks carry the agents for Powassan disease and a new form of human ehrlichiosis. American dog ticks (“wood ticks”), which are very common in spring and early summer throughout Minnesota, can carry Rocky Mountain spotted fever (RMSF).

While RMSF is most common in the southern United States, a small number of RMSF cases have occurred in Minnesotans who did not travel outside the state.

More information about Minnesota’s tick-borne diseases, including signs, symptoms, and prevention, is available at or by calling MDH at 651-201-5414.