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Influenza activity is declining nationally, but remains high in parts of the country and may continue for some time. This season has been severe for people 65 and older with key indicators showing many hospitalizations and deaths in that age group. CDC recommends that high risk persons, including seniors, seek care as soon as possible for flu symptoms because antiviral treatment can avert serious flu outcomes.

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There are many different influenza A Viruses; some are found in humans and others in animals such as avian flu in birds and poultry.



Influenza viruses that normally circulate in pigs are called “variant” viruses when they are found in people. Influenza A H3N2 variant viruses (also known as “H3N2v” viruses) with the matrix (M) gene from the 2009 H1N1 pandemic virus were first detected in people in July 2011.



There are many different influenza A Viruses; some are found in humans and others in animals such as swine flu in pigs.



CDC’s pandemic preparedness efforts include ongoing surveillance of human and animal influenza viruses, risk assessments of influenza viruses with pandemic potential, and the development and improvement of preparedness tools that can aid public health practitioners in the event of an influenza pandemic.



Bat influenza refers to influenza A viruses found in bats. Laboratory research at CDC suggests these viruses would need to undergo significant changes to become capable of infecting and spreading easily among humans. Little yellow shouldered bats are not native to the continental United States, but are common in Central and South America.



Dog flu is a contagious respiratory disease in dogs caused by a specific Type A influenza virus referred to as a “canine influenza virus.” This is a disease of dogs, not of humans.



Influenza A viruses are found in humans and many different animals, including ducks, chickens, pigs, whales, horses and seals. Additional information on 2009 H1N1 influenza,, and Nonpharmaceutical Interventions (NPIs).



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