Legionellaceae

Legionellaceae is a family of Gram-negative bacteria that includes the genus Legionella, which contains over 60 species. The most well-known species is Legionella pneumophila, the causative agent of Legionnaires' disease and Pontiac fever.

Taxonomy

The family Legionellaceae was first described in 1979 and is part of the order Legionellales. It currently consists of a single genus, Legionella, which was first described in 1978. The genus Legionella is further divided into several species, the most notable of which is Legionella pneumophila.

Characteristics

Legionellaceae are aerobic bacteria that require oxygen to grow. They are Gram-negative bacteria, meaning they do not retain the violet stain used in the Gram stain procedure. Instead, they take up the red counterstain. They are also rod-shaped and can be either motile or non-motile.

Pathogenesis

Members of the Legionellaceae family are primarily known for their role in human disease. Legionella pneumophila, in particular, is a significant human pathogen. It is the causative agent of Legionnaires' disease, a severe form of pneumonia, and Pontiac fever, a milder illness resembling the flu.

Epidemiology

Legionellaceae are found worldwide in both natural and man-made environments. They are particularly prevalent in warm water environments, such as hot tubs, cooling towers, and large plumbing systems. Humans typically become infected by inhaling aerosolized water droplets containing the bacteria.

Treatment

Treatment for infections caused by Legionellaceae typically involves antibiotics. Macrolides, quinolones, and rifampicin are among the most commonly used.

Prevention

Prevention of Legionellaceae infections primarily involves proper maintenance of water systems to prevent the growth and spread of the bacteria.

File:Legionella pneumophila SEM.jpg

Legionella pneumophila under a scanning electron microscope

See also

• List of bacterial families
• Bacterial taxonomy