The news many in the U.S. were waiting for…this week ACIP and the CDC authorized booster shots for eligible Moderna and Johnson & Johnson recipients.


➡️ Booster recommended for *ALL* Johnson & Johnson one-dose vaccine recipients at least two months past their shot.


Everyone, including J&J recipients, can choose a vaccine different from their primary series.

❓So which booster should you get?

Any combination is authorized, but based on the current immunological data some combinations produce a higher antibody boost.

Best options:

💉 Moderna or Pfizer primary series → Moderna or Pfizer booster

💉 Johnson & Johnson → Moderna/Pfizer booster

Moderna *might* induce slightly more antibodies than Pfizer if you have a choice, but the two are very similar. Also the mix and match trials used a full dose of Moderna rather than the half dose that was authorized as a booster so it’s not known how the half dose directly compares to Pfizer.

You can get a second Johnson & Johnson dose which does boost antibodies, but an mRNA booster produced a higher antibody response in mix and match trials.

Getting a Johnson & Johnson shot AFTER an mRNA vaccine did not produce as high of antibodies as two mRNA vaccines.

❓But do I NEED a booster? We think the evidence is accumulating that these vaccines may indeed be better as three-dose vaccines. Pfizer released some data this week (via press release) showing randomized trial data that a 3rd dose reduced the risk of symptomatic COVID-19 infection 95.6% COMPARED TO PEOPLE WITH 2 DOSES. While we await the full data, that is a REMARKABLE effect.

So if you are in one of the eligible categories (see figure and CDC link below) and 6 months past your primary series (or 2 months for J&J), GO GET THAT BOOST!

Those Nerdy Girls

Should You Mix and Match Your Booster Shot?

FDA authorizes booster shots of Moderna, Johnson & Johnson Covid-19 vaccines

Who is eligible for a booster?

Pfizer booster trial Press Release

Previous DP post on new “Mix and Match” data

Link to Original FB Post