Twelve cases of the bacteria-caused illness were discovered about three weeks ago among people who had spent time in Anaheim and included nine people who had visited Disneyland in September before developing the illness, according to the Orange County Health Care Agency. Their ages ranged from 52 to 94.
The remaining three were Orange County residents who did not visit the park but lived or traveled in Anaheim.
Ten were hospitalized and one person "with additional health issues" died, according to health officials. That person did not visit Disneyland.
Legionnaires' is a severe lung infection caused by exposure to contaminated water or mist. Authorities said they have not tied any other cases of Legionnaires' to Anaheim since September.