The JW Marriott Hotel and city health officials are notifying the 8,500 guests who stayed at that hotel on West Adams between July 16 and August 15.
Authorities believe the source of the bacteria may have been the swimming pool, the whirlpool and a fountain. They have all been drained and sanitized, and no longer pose a health risk.
Legionnaires' disease is a severe form of pneumonia contracted by inhaling the bacteria in water vapor. It cannot be spread from person-to-person. Most people who are exposed to it do not get sick.