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ShadowWolf WRONG. I'm guessing you're not raising kids.
The MMR vaccine, combining vaccines for measles, mumps, and rubella, was released 50 years ago in 1971. By 1980, all US states had adopted requirements for mandatory MMR vaccinations for public school; these days it's a 2-dose regimen.
The Tdap vaccine - a follow-on the early childhood 5-dose DTaP - was released in 2005, and, like MMR, is required in all US states for public school.
https://www.healthline.com/health-news/vaccine-mandates-in-schools-arent-new-theyve-been-used-since-1850#A-history-of-vaccine-mandates-in-schoolsTwo doses for MMR - sure sounds like a booster to me.
Five doses for Tdap DTaP - definitely a booster there.
FYI the polio vaccine requires four doses.
CDC recommends that children get four doses of polio vaccine. They should get one dose at each of the following ages: 2 months old, 4 months old, 6 through 18 months old, and 4 through 6 years old.
Are you certain the Ebola vaccine doesn't require a booster? You just made some guesses about other vaccines and the guesses were wrong.