Vaccinate your pets, say Cook County officials. The reason? They've found seven rabid bats in Chicago alone (and 19 in the county as a whole). If left untreated, rabies is almost always fatal—but vaccines are cheap and easily available.
Steep Decline in Bat Population Forces Wisconsin State Park to End Bat Watch
The little brown bat population at Devil's Lake State Park dropped from 200 to 20 in one year thanks to white-nose syndrome.