San Quentin doesn't believe that it was the result of a person-to-person spread. No quarantine has been announced at this time, and the inmate is said to be in stable condition.
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The rehabilitation center has a medical unit at the prison, but a representative told ABC7 Eyewitness News that she didn't know whether the inmate was still being treated at the medical unit or was returned to his regular housing facility.
San Quentin said it has not seen any other cases of suspected hantavirus on the premises.