Legionellosis is a collective term for the diseases caused by legionella bacteria. It includes the most serious, Legionnaires’ disease, as well as the similar but less serious conditions of Pontiac fever and Lochgoilhead fever.
Legionnaires’ disease is a potentially fatal pneumonia-like illness, with no known vaccine. It is not known to spread from person to person. The symptoms of Legionnaires' disease are similar to the symptoms of the flu and include:
Pontiac and Lochgoilhead fever are less serious conditions with milder flu-like symptoms.
Although everyone is susceptible to infection by breathing in legionella bacteria, the risk increases with age and some people are at higher risk than others including:
People inhale the bacteria when it spreads in small droplets of water suspended in the air (aerosols).
The health risks from legionella bacteria are insignificant when growth of the bacteria and exposure to aerosols are adequately controlled.
