If one flu shot is good, wouldn’t two be better?
Can I Get a Second Flu Shot for Extra Protection?
Some people do get a second flu shot.
In fact, all kids eight years and younger, if it is their first time getting a flu vaccine, get two doses of flu vaccine.
The first dose is a priming dose and the second, at least 28 days later, is a booster dose.
Why do we do it that way?
Because studies have shown that is the best way to do it.
We don’t need to use this same priming/booster strategy in older children and adults though.
But with recent talk that protection against the flu after a flu vaccine might wane before the end of a flu season, some folks are likely wondering if they should just get another flu shot later in the season.
“Revaccination later in the season of persons who have already been fully vaccinated is not recommended.”
Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices—United States, 2018–19 Influenza Season
And the official answer is no, except for younger children getting vaccinated for the first time, you should just get one dose per season.
Why not?
Mostly because a lot of studies haven’t been done to see what effect that second dose will have. And since some studies have even suggested that regular annual flu vaccines could actually lower vaccine effectiveness, you would want to know if getting an extra flu vaccine was safe and effective before we started to do it.
Not surprisingly, someone has looked into this already. One small study, Influenza revaccination of elderly travelers: antibody response to single influenza vaccination and revaccination at 12 weeks, actually showed that a second dose in the same season “did not enhance the immune response.”
So just one flu vaccine per season.
“Prior-season vaccination history was not associated with reduced vaccine effectiveness in children, supporting current recommendations for annual influenza vaccination of children.”
McLean et al on Association of Prior Vaccination With Influenza Vaccine Effectiveness in Children Receiving Live Attenuated or Inactivated Vaccine
But do get a flu vaccine every season.
Again, while there were some reports that an annual flu vaccine could lower vaccine effectiveness, other studies have disproven this.
More on Getting a Second Flu Shot
- VAXOPEDIA – How Many Doses of Flu Vaccines Do My Kids Need?
- VAXOPEDIA – When Should I Get My Flu Shot?
- VAXOPEDIA – Is This Year’s Flu Vaccine Working?
- VAXOPEDIA – I’m Not Anti-Vaccine, I Just Don’t Believe in Flu Shots
- VAXOPEDIA – Do They Really Just Guess at Which Strain to Put in the Flu Vaccine?
- VAXOPEDIA – Can Flu Shots Cause the Flu?
- VAXOPEDIA – Does Getting a Flu Vaccine Increase Your Risk of Spreading the Flu or Getting Others Sick?
- VAXOPEDIA – I Refuse to Listen to Bad Advice About Flu Shots, and I Won’t Apologize for It
- MMWR – Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices—United States, 2018–19 Influenza Season
- Ask the Experts about Flu Vaccines
- Guide for Determining the Number of Doses of Influenza Vaccine to Give to Children Age 6 Months Through 8 Years
- Why Some Kids Need a Second Dose Of Flu Vaccine
- Study – Immunogenicity and reactogenicity of 1 versus 2 doses of trivalent inactivated influenza vaccine in vaccine-naive 5-8-year-old children.
- Study – Influenza Vaccine Effectiveness for Fully and Partially Vaccinated Children 6 months to 8 Years Old during 2011–2012 and 2012–2013: The Importance of Two Priming Doses
- Study – Influenza Revaccination of Elderly Travelers: Antibody Response to Single Influenza Vaccination and Revaccination at 12 Weeks
- Study – Increasing herd immunity with influenza revaccination.
- Study – Different Repeat Annual Influenza Vaccinations Improve the Antibody Response to Drifted Influenza Strains
- Study – Repeated influenza vaccination for preventing severe and fatal influenza infection in older adults: a multicentre case-control study.
- Study – Association of Prior Vaccination With Influenza Vaccine Effectiveness in Children Receiving Live Attenuated or Inactivated Vaccine