So far, there have been eight confirmed cases of the illness — two of which were fatal — among some 8,500 guests who stayed at the hotel at 151 W. Adams St. from mid-July to mid-August, according to the Chicago Department of Public Health.
It is the worst kind of publicity for any hotel, not to mention one as new as the JW Marriott, a 610-unit high-end hotel that Chicago developer Michael Reschke completed in November 2010.
Since the first cases were reported earlier this month, the hotel has worked with health officials to identify the source of the outbreak, draining its fountain, pool and hot tub, whose water could serve as a breeding ground for Legionella bacteria.
Named after an outbreak at an American Legion convention in 1976, Legionnaire's disease is a severe type of pneumonia caused by the Legionella bacteria, which thrive in warm water, according to the city health deparment. Individuals get the disease by breathing in small droplets of water contaminated with the bacteria. Between 5 percent and 30 percent of cases are fatal.
The city spokeswoman said an average of 30 individual cases of the disease are reported in Chicago each year, meaning they are not linked to a common source.
