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Influenza (Flu) Viruses

There are two main types of influenza (flu) virus: Types A and B. The influenza A and B viruses that routinely spread in people (human influenza viruses) are responsible for seasonal flu epidemics each year. Influenza A viruses can be broken down into sub-types depending on the genes that make up the surface proteins. Over the course of a flu season, different types (A & B) and subtypes (influenza A) of influenza circulate and cause illness.

More Information about Flu Viruses

Questions & Answers about Flu Viruses

 

 Health Insurance Marketplace. Marketplace plans cover free flu vaccines. http://www.healthcare.gov

The Flu I.Q. widget is an interactive quiz to test your flu knowledge.
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