They aren’t perfect though, which is why some vaccines need booster doses to help them provide long lasting protection.
Why Do Some Vaccines Need Boosters?
To be clear, just because you get more than one dose of a vaccine, that doesn’t make it a booster dose.
For example, infants get multiple doses of the DTaP, polio, Hib, hepatitis B, Prevnar, and rotavirus vaccines, but those are part of the primary series for those vaccines. They aren’t boosters.
“A “classical” prime-boost immunization schedule is, thus, to allow 4 to 6 months to elapse between priming and booster doses, hence the generic “0-1-6 month” (prime-prime-boost) schedule. Secondary antigen exposure thus results in the production of higher-affinity antibodies than primary responses.”
Plotkin’s Vaccines (Seventh Edition)
Classic booster doses are the:
- 4th and 5th dose of DTaP
- 2nd dose of hepatitis A
- 3rd dose of hepatitis B
- 4th dose of Hib
- 3rd dose of HPV
- 4th dose of Prevnar
- 4th dose of polio
- 2nd dose of meningococcal vaccines
- most Tdap doses (if you are not due for a Tdap booster and are getting a dose because you are pregnant, than that probably wouldn’t be considered a booster dose)
- 2nd dose of Varivax (chicken pox vaccine)
But why do we need these booster doses?
While one or more doses of the primary series of the vaccine leads to the production of plasma cells and protective antibodies, the booster dose then causes a secondary immune response and the production of more long-lived plasma cells. That’s how we get higher levels of protective antibodies that will last longer.
Which Vaccines Don’t Need Boosters?
In general, live vaccines don’t need booster doses.
So why do we get a second dose of MMR?
This isn’t a classic booster dose. It protects the small percentage of people who don’t respond to the first dose.
What to Know About Vaccine Booster Doses
Some vaccines need booster doses to help you get full protection. Don’t skip them.