One of the reasons people choose not to get a flu shot each year is because they believe it is not effective. The flu virus changes from season to season, this sometimes makes it challenging to measure its effectiveness. Recent CDC studies show a flu vaccine reduces the risk of getting the flu between 40%-60% among the overall population. During the years when there is a good match between the flu vaccine and circulating viruses, it is possible to measure substantial benefits from a flu vaccination when it comes to preventing flu illness and complications.  Learn more about the CDC flu vaccine effectiveness here

As mentioned above, unlike what we know so far about COVID-19, the flu virus changes each year. It is important for the CDC to measure vaccine effectiveness to help future flu seasons. The CDC measures a vaccines effectiveness by using the following criteria:

  • Ability to prevent flu-related trips to the doctor
  • Limiting the need for hospitalization
  • Ability to protect against identified seasonal strains
  • Ability to protect different age groups from flu
  • Ability to protect special populations from flu

Effectiveness of flu vaccines in elderly and children

According to the CDC, if you are 65 or older, getting a flu vaccine reduces the risk of a medically attended illness caused by the flu virus by 60% and the risk of flu hospitalizations by 54%. If an elderly person has a weaker immune system, getting vaccinated against the flu can decrease the chances of becoming seriously ill, requiring hospitalization, or even dying.

Flu vaccination in children has been found to provide a similar level of protection against flu illness as seen in healthy adults. For children up to 8 years old it is recommended they receive 2 doses of flu vaccine the first time they are vaccinated against the flu (each dose should be separated by 4 weeks).

For more information on how vaccine effectiveness is measured, visit the CDC website here