Legionnaires' disease acquired its name in July 1976, when an outbreak of pneumonia occurred among people attending a convention of the American Legion at the Bellevue-Stratford Hotel in Philadelphia. Of the 182 reported cases, mostly men, 29 died. On January 18, 1977, the causative agent was identified as a previously unknown strain of bacteria, subsequently named "Legionella", and the species that caused the outbreak was named "Legionella pneumophila". Outbreaks of Legionnaires' disease receive significant media attention, but this disease usually occurs in single, isolated cases not associated with any recognized outbreak. When outbreaks do occur, they are usually in the summer and
Epidemiology of pneumonia Epidemiology of pneumonia Pneumonia is a common illness affecting approximately 450 million people a year and occurring in all parts of the world. It is a major cause of death among all age groups, resulting in 1.4 million deaths in 2010 (7% of the worlds yearly total) and was the 4th leading cause of death in the world in 2016, resulting in 30 million deaths worldwide. Pneumonia is a type of lower respiratory tract infection, and is also the most deadly communicable disease as of 2016. Rates are greatest in children less than five and adults older than 75 years