The Public Health Department says it believes the patient was bitten by a bat in Merced County.
Officials are now notifying individuals who may have been exposed, as well as preparing medical providers in the community on response measures.
Rabies is a fatal disease caused by a virus that attacks the brain and nervous system.
In the United States, more than 90% of rabies cases are from a wild animal.
Action News spoke with Dr. Geetha Sivasubramanian with UCSF Fresno, who said seven out of 10 people who get infected with rabies get the virus from a bat.
Potentially tragic outcomes can be prevented if an exposed person or animal receives a series of rabies vaccine shots.
They should get them as soon as possible after the exposure, even if there are no symptoms.