Influenza

Influenza (or as it is commonly known, the flu or the grippe) is a contagious disease, caused by an RNA virus of the orthomyxoviridae family. It rapidly spreads around the world in seasonal epidemics, imposing considerable economic burden, in the form of health care costs and lost productivity. Major genetic changes in the virus have caused three influenza pandemics in the 20th century, killing millions of people. The name comes from the old medical belief that unfavourable astrological influences cause the disease.

See also

• Infectious diseases
• Avian influenza
• Spanish flu
• Pandemic