Headline:Illustration of Antigenic Shift of the Influzena Virus [Image]

Description:From introduction: The genetic change that enables a flu strain to jump from one animal species to another, including humans, is called antigenic shift. Antigenic shift can happen in three ways. Antigentic 1: a) A duck or other aquatic bird passes a bird strain of influenza A to an intermediate host such as a chicken or pig; b) A person passes a human strain of influenza A to the same chicken or pig; c) When the viruses infect the same cell, the genes from the bird strain mix with genes from the human strain to yield a new strain; or d) The new strain can spread from the intermediate host to humans. Antigenic Shift 2: Without undergoing genetic change, a bird strain of influenza A can jump directly from a duck or other aquatic bird to humans. Antigenic Shift 3: Without undergoing genetic change, a bird strain of influenza A can jump directly from a duck or other aquatic bird to an intermediate animal host and then to humans. The new strain may further evolve to spread from person to person. If so, a flu pandemic could arise.

Authors:National Institutes of Health. National Institute of Allergy and Infectious Diseases 

Publishers:National Institute of Allergy and Infectious Diseases. Division of Microbiology and Infectious Diseases 

Rights Management:Public Domain

Disease Names:Avian Influenza 

Disease Aspects:Genetics 

Resource Types:Illustrations 

Resource Formats:URL 

Languages:English 

Technical Level:Non-Technical 

Keywords:Avian influenza Genetic diversity Influenza A Virus