BEMIDJI — A summer of heavy rains has caused a rise in cases of a rare fungal infection in northern Minnesota.

So far this year, more than 45 people and 150 animals have been diagnosed with blastomycosis. Last year, only 31 human cases and fewer than 100 animal infections were reported by this time.

An epidemiologist with the Minnesota Department of Health, Malia Ireland, said the infections are caused by fungi living in the ground.

Ireland said flooding has moved land around, exposing spores to the air.

The fungus thrives in moist ground, especially in wooded areas near rivers and lakes. Most of the cases were reported in northern Minnesota.

Most of the animal cases are dogs, which dig their noses in the dirt.