Why does the cdc tell you get the rabies shot if you wake up with a bat in your room?

Why does the cdc tell you get the rabies shot if you wake up with a bat in your room? What if you wake up bat in your room but you didn't see it or hear it, and just never knew about it?

Why does the cdc tell you get the rabies shot if you wake up with a bat in your room?
Post Opinion