Are there different types of flu viruses?
Researchers divide flu viruses into three general categories: types A, B and C. All three types can mutate, or change into new strains, and type A influenza mutates often, yielding new strains of the virus every few years. This means that you can never develop a permanent immunity to influenza. Even if you develop antibodies against a flu virus one year, those antibodies are unlikely to protect you against a new strain of the flu virus the next year. Type A mutations are responsible for major flu epidemics every few years. Type B is less common and generally results in milder cases of flu. However, major flu epidemics can occur with type B every three to five years. Type C causes infection but does not cause typical flu symptoms. Both influenza A and B have been linked to the development of Reye’s syndrome, a potentially fatal complication that usually affects children and teens under 18. Widespread outbreaks of Reye’s syndrome have occurred with influenza type B and also with chickenp
