Under the decision from Centers for Disease Control and Prevention director Rochelle Walensky, eligible people can get any of the three available booster doses, regardless of which shot they received first. The Food and Drug Administration
authorized the additional shots Wednesday.
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Any booster shot, even if it is the same as your first vaccine, will increase the number of antibodies that can fight the coronavirus. But, in some cases, mixing vaccines may offer better protection, experts say. Early data has shown that following up a first dose of Johnson & Johnson with an mRNA vaccine — Moderna or Pfizer — provided significantly higher levels of neutralizing antibodies.
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For people who received either Moderna or Pfizer, experts say it is both safe and effective to stick to the same vaccine.