If you have a heavy population, there is also a multi-disease danger from a large accumulation of their droppings. The danger is actually small, but however small, there is always a danger, and as with any wild animal, you don't want them close to your house. Suffice to say, if you are bitten by ANY animal, you are wise to seek the help of a medical doctor immediately. If the animal is available, it should also be held for tests. The symptoms of rabies develop faster if the bite is closer to the head.
Rabies affects the brain and the spinal cord and eventually causes death in any animal.
These little fellows are one of the many beneficial animals that actually help us. Don't feed birds or other wild animals, nor habituate them to humans. This is Naturalist Rule Number One. Okay, so you discover you have a bat inside. Flying around, fast, all over the place.