The best method is to make your home less appealing. First try using bright lights in the area that they prefer to roost. Most bats prefer dark areas when searching for a potential roost site. Both methods are very effective but always first consider keeping the bats. Aside from being a wonderful conversation piece they will also control the insect population in your neighborhood.
Many mammals carry rabies.
In the western United States the Coyote, Gray Fox, and the Striped Skunk are the most common carriers of the rabies virus. Most bats are insectivorous which means that they eat insects. A large colony of this species can consume over 200 tons of insects nightly. For example, the bulldog bat found primarily in the tropics, is a fish-eating specialist. Only Vampire bats feed on blood from other animals.