The Milwaukee health department is warning residents to take steps to prevent exposure to rabies.
The department said it has confirmed a positive test of rabies in a bat that was captured after being found in a household and coming into contact with an adult.
Rabies can be transmitted to humans through a bite, scratch or when animal saliva comes into contact with broken skin.
The department said if people find an animal that may be infected in a home, they should safely capture the animal until a health official can be consulted.
The department advises people to avoid contact with wild animals, vaccinate domestic dogs and cats against rabies, keep screens in good repair and close small openings which bats may enter.