ABC, the Flu Virus Comes in Three
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Understanding the flu virus
Not all flu viruses are the same, and even the same flu virus can affect each person differently. Some types of flu can infect animals as well as people while other types only infect people. Influenza viruses constantly change or mutate on their own, or by crossing with another strain, usually from birds or pigs.
The three main types of flu viruses are A, B and C. Types A and B are the viruses most responsible for flu outbreaks each flu season. Type C viruses cause milder illness and don’t cause epidemics.
The flu shot is a yearly injection that protects you from types A and B.
Flu virus type A
The influenza virus type A can infect both animals and humans. It is the most serious of flu viruses causing widespread outbreaks worldwide (pandemics).
Type A viruses are classified into subtypes based on 2 types of proteins found on the surface of the virus, HA proteins (1 through 18) and NA proteins (1 through 11). An example of a type A influenza subtype is H1N1, also known swine flu. Three HA subtypes (H1, H2 and H3) and two NA subtypes (N1 and N2) are known to cause the most widespread human disease.
For this flu season, experts believe that two main influenza A subtypes (H1N1 and H3N2) will cause the most infections.
Type A flu viruses change/mutate constantly, creating new strains of the virus and the need to develop new vaccines each flu season.
Flu virus type B
Flu virus type C
This information should not be used as a substitute for the medical care and advice of your doctor. There may be variations in treatment that your physician may recommend based on individual facts and circumstances. If you have questions about your symptoms, ask the Pharmacist at Walmart for more information, and/or contact your doctor.
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