Legionnaires' disease Legion convention in 1976 was high (29 deaths in 182 infected individuals) because the antibiotics used (including penicillins, cephalosporins, and aminoglycosides) had poor intracellular penetration. Mortality has plunged to less than 5% if therapy is started quickly. Delay in giving the appropriate antibiotic leads to higher mortality. The fatality rate of Legionnaires' disease has ranged from 5 to 30% during various outbreaks and approaches 50% for nosocomial infections, especially when treatment with antibiotics is delayed. Hospital-acquired "Legionella" pneumonia has a fatality rate of 28%, and the principal source of infection in such cases is the drinking-water distribution system. Legionnaires' disease
1976 Philadelphia Legionnaires' disease outbreak which then spread it through the building. This finding prompted new regulations worldwide for climate control systems. Complicating the situation was a fear among the public that the original cluster of 14 cases, six of whom died within a few days of each other, represented an outbreak of swine flu. The total number of cases reached 211, and of those, 29 had died. At the time of the outbreak, epidemiological investigation protocols did not include active participation by both the laboratory specialists and investigators. No effective communication existed between scientists in the field interviewing patients, and those in the laboratory