Legionella

Legionella infection is one of the more serious pneumonias. The mortality rate in hospitals is five to 35 percent. Aerosolisation from contaminated water sources is the source of infection. Person to person infection does not occur. The disease manifests after two days or two weeks. A mild form, which goes by the fashionable name of Pontiac fever, is a flu-like illness that goes away on its own in five to seven days. Unless the doctor looks out and tests for Legionella, these cases are invariably missed and put down as just "flu" or "viral fever". The more serious illness usually presents with history of high fever and chills. Cough is usually dry but associated with breathlessness.