The disease has killed more than 5.7 million cave-dwelling bats in the eastern third of North America. It has been spreading south and west.
Illinois and several other Midwestern states are home to many endangered bat species and some of the largest hibernating bat populations in the country.
Bats play a critical environmental role, gobbling up thousands of tons of potentially harmful forest and agricultural pests each year, including mosquitos.
While researchers search for a way to fight white-nose syndrome, federal and state officials have focused on trying to contain the disease.
The Illinois Department of Natural Resources has kept caves it owns or manages closed because officials believe the fungus that causes the disease can be carried among caves by humans on clothing, footwear and caving gear.