The Iowa Department of Public Health says the woman reported a bat in her house but wasn't too worried about it. She turned on her automatic coffee maker before bedtime and drank her coffee the next morning.
She discovered the bat in the filter when she went to clean it that night. The woman has undergone treatment for possible rabies.
Health officials say that the bat was sent to a lab but that its brain was too cooked by the hot water to determine whether it had rabies.