The Bellevue-Stratford Hotel in July 1976, when it hosted a statewide convention of the American Legion. Soon after, a pneumonia-like disease killed 29 people and sickened 182 more who had been in the hotel. The vast majority were members of the convention. The negative publicity associated with what became known as "Legionnaires' Disease" caused occupancy at the Bellevue-Stratford to plummet to 4 percent and the hotel finally closed on November 18, 1976. In 1977, Dr. Joseph McDade discovered a new bacterium, which was identified as the causative organism. It thrives in hot, damp places like the water of the cooling towers for the
1976 Philadelphia Legionnaires' disease outbreak 25 had died. Both the first week and later, there were 149 Legionnaires who became sick and 33 other persons associated with the hotel or in the area who also became sick. Of these total of 182 cases, 29 persons died. The U.S. Centers for Disease Control and Prevention mounted an unprecedented investigation and, by September, the focus had shifted from outside causes, such as a disease carrier, to the hotel environment itself. In January 1977, the "Legionella" bacterium was finally identified and isolated and was found to be breeding in the cooling tower of the hotel’s air conditioning system,