The flu shot is made from inactivated (killed) flu viruses, which cannot cause infection. The preparation is based on the flu viruses that are in circulation at the time and on the viruses that are expected to circulate the following winter. The flu shot is something that you must do yearly because it changes every year as the viruses change.
What Is a Flu Shot?
The main way to keep from getting the flu is to get a yearly flu shot. You can get this at:
- Your doctor's office
- A local clinic
- Work (in many communities)
It is important to note that you must get the flu shot every year because it is different every year.
How the Flu Shot Is Made
Scientists make a different flu shot every year because the strains of flu viruses change from year to year. Nine to ten months before the flu season begins, scientists will prepare a new shot made from inactivated (killed) flu viruses. Because the viruses are inactive, they cannot cause infection. The preparation is based on the flu viruses that are in circulation at the time and the viruses that are expected to circulate the following winter.
It is important to note that an unpredicted new strain of the flu virus may appear after the flu shot has been made and distributed to doctors' offices and clinics. This means that even if you get the shot, you still may get infected. However, if you do get infected, the disease is usually milder because the flu shot will still give you some protection.