Recent Blog Articles
Why eat lower on the seafood chain?
Can long COVID affect the gut?
When replenishing fluids, does milk beat water?
Safe, joyful movement for people of all weights
Slowing down racing thoughts
Are women turning to cannabis for menopause symptom relief?
3 ways to create community and counter loneliness
Helping children make friends: What parents can do
Can electrical brain stimulation boost attention, memory, and more?
Palliative care frightens some people: Here’s how it helps
Why do we need new flu shots every year?
- By Anthony L. Komaroff, MD, Editor in Chief, Harvard Health Letter
Ask the doctor
Q. It’s flu shot time again. With all of these new ways of making vaccines, why do we still need a new shot each year? Why can’t we get one flu shot that will protect us for the rest of our lives?
A. Many scientists are working on developing just such a "universal" vaccine for the influenza (flu) virus. Why do we need a new shot every year? The influenza virus, like every virus, contains a set of genes that are wrapped in a coat of protein. Vaccines typically stimulate the production of antibodies that attach to outer structures on the protein coat, disabling the virus; indeed, that’s how the influenza vaccine works. Unfortunately, these outer structures are constantly changing, so a new vaccine is needed each year to target those structures on the flu viruses that are currently circulating. In recent years, scientists have found inner structures in the influenza virus protein coat that are the same in all strains of flu viruses. Universal vaccines that target those inner structures hold the promise of protecting against different types of influenza virus, eliminating the need for a new shot every year. Even more important than avoiding the hassle of an annual flu shot, a universal flu vaccine could be ready immediately and in large quantities — without the usual multi-month delay needed to create and produce a vaccine — when a deadly new pandemic flu virus emerges, as history says it will. I’m optimistic that remarkable scientific progress under way will give us a universal flu vaccine in the next 10 to 20 years.
To continue reading this article, you must log in.
Subscribe to Harvard Health Online for immediate access to health news and information from Harvard Medical School.
- Research health conditions
- Check your symptoms
- Prepare for a doctor's visit or test
- Find the best treatments and procedures for you
- Explore options for better nutrition and exercise
I'd like to receive access to Harvard Health Online for only $4.99 a month.Sign Me Up
Already a member? Login ».
About the Author
Anthony L. Komaroff, MD, Editor in Chief, Harvard Health Letter
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles.
No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.
You might also be interested in…
COVID-19, Flu, and Colds
Any given year, we’ll collectively come down with one billion colds and up to 45 million cases of flu, while the number of new cases of COVID-19 keeps rising. In this guide, you will learn how to avoid getting any of these three viral infections, and, if you do get sick, what you can do to feel better. You’ll also learn when your condition is serious enough to call a doctor. The report also provides specific information about high-risk groups for whom COVID and the flu can be very serious.
Free Healthbeat Signup
Get the latest in health news delivered to your inbox!