The agency says four cases have been reported at the Lady Minto Hospital acute care centre, prompting the declaration of an outbreak at the hospital.
One of the four patients to contract the infection has died, but the authority says the disease wasn't a factor in the death.
The other three patients remain in hospital and have either responded or are responding to treatment.
The authority says the newest cases are believed to have occurred within the facility.
The Vancouver Island Health Authority says its rate of C. difficile is lower than the provincial average and staff screens for any possible infection by looking for symptoms before people are admitted.