Flu shot effectiveness Q&A: When to get it, how long does it work?

Flu season is here again and many people have questions about flu shot effectiveness and the best time to get the shot. Because the flu can be such a devastating disease a flu shot is an important part of your preventative health care each year.

Why should I get a flu shot?

In a nutshell says the Centers for Disease Control and Prevention (CDC) the flu shot is the best way to prevent the disease. The CDC goes on to point out that since millions of people come down with the flu each year resulting in hundreds of thousands of hospitalizations and thousands of deaths it's important to take this step to protect yourself and your family from getting sick and to prevent the virus spreading to others.

Why do I need to get a flu shot every year?

There are multiple reasons why people should receive a flu shot for each flu season.

First the flu shot itself may change according to the viruses that are projected to be circulating each season. The CDC explains many flu shots this year are quadrivalent meaning they contain protection against four different viruses two A strains and two B strains. In past years a trivalent vaccine has been offered providing protection against two A strains and only one B strain. The flu viruses covered by the vaccine have been updated this season says the CDC to match what researchers believe will be circulating in the coming months.

The CDC also projects flu shots will become less effective over the course of the season though the actual duration of vaccine protection continues to be studied and may even vary across age groups. So even if you received the shot last year you'll need another one this year for full protection.

When is flu season?

The flu season may extend from late October all the way to March with the flu at its peak typically from December to March. Getting your flu shot before this time can help protect you against the flu and prevent it from spreading to others.

Do I need a booster shot?

The short answer is probably not. A yearly flu immunization should be sufficient protection. However children age six months to eight years who are receiving a flu shot for the first time should receive two shots at least four weeks apart to develop immunity. The CDC describes this process: The first shot primes the body for immunization while the second actually creates the desired immune response. Senior citizens may also want to consider requesting Fluzone high-dose which creates a greater immune response and as a study in the New England Journal of Medicine suggests may provide greater protection against the flu.

When should I get the flu shot?

Because the body takes about two weeks to develop immunity after receiving the shot the CDC recommends the shot be administered by the end of October in the event of an early flu season. But if you missed getting the shot in October you should still get it all the way through the flu season and as long as the vaccine is available.

If you have more questions about flu shot effectiveness you should ask your primary care provider or consult the CDC's website a valuable resource for flu-related information and statistics.