The influenza flu virus can change overall genetic structure every year which makes it difficult for medical science to create a single vaccine for treating the disease. This is a huge challenge faced by medical science.
Every year, World Health Organization monitors each and every strain of new influenza virus as soon as it appears along with the Centers for Disease Control and Prevention which helps them in assessing the dominant virus in the current year season. This data is then taken by scientists for developing a particular vaccine, each and every year, against the specific strain of new virus that they think would be dominant.
MORE ABOUT THE VIRUS
The influenza virus is a virus that confuses the human immune response since it undergoes quick mutations which renders it impossible for recognition. Influenza is not only a serious disease that can cause hospitalization of the patient but albeit a deadly one. People tend to suffer from flu every single year with varied flu pattern.
Millions of people get flu virus every year but the type is always different. The flu virus can also affect immune system of a very healthy person. In the United States, the flu virus is very common and causes several thousands of deaths every year.
THE EVER CHANGING FLU VIRUS
Influenza viruses constantly change over time. But the pattern of change is of two types- antigenic drift and antigenic shift.
- Antigenic Drift: small changes in the genes of the flu virus occur over time with replication of the virus. The genetic changes cause the production of similar viruses which share same kind of antigenic properties. The immune system can respond to such changes by recognizing it. But accumulation of such changes over time can cause the virus to become very different from each other which renders the response of the immune system useless.
- Antigenic Shift: this is a major and abrupt change in the flu virus. This causes a new kind of virus to suddenly emerge. Humans don’t possess any kind of immunity against this new kind of virus and tend to get affected.
THE MAIN CONCERN
Genetic changes in the flu virus are majorly responsible for why people can acquire influenza flu more than once. This is also the major reason why flu vaccine gets renewed and reviewed each and every year for being updated according to the evolved virus.