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mmr vaccine
dawndave posted:
The middle school where my daughter attends told us that her second dose of mmr vaccine was given when she was 3, has been given when she was to young so they want her to get a third vaccine of it. Is it harmful?
Roy Benaroch, MD responded:
Wow, we get more vaccine questions here than anything else! I don't mind-- keep 'em coming!

Would it be harmful? No. An extra dose isn't extra-dangerous, and has no more chance of side effects than any other routine vaccine.

However, having had the second dose at age 3 is NOT too early. CDC guidelines recommend a first dose of MMR at about age 1 (actually, any time after the 12 month birthday), and a second dose 4 weeks or more after the first dose. That second dose is traditionally given at age 4-5, but can be given earlier. As long as it is 4 weeks or more past the 1st dose, it "counts", and does NOT need to be repeated at age 4.

This is the official CDC recommendation for vaccine schedule for children:

Note footnote 8 about MMR timing.

Now, private schools are free to make their own policies; and even public schools may follow their own school board recs that may not exactly match the "official" CDC rec. Still, that CDC rec really should be the best resource for parents and pediatricians and schools to follow.

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