More than 50 million Americans have received at least one dose of either the Pfizer or Moderna Covid-19 vaccine. So far, Americans have been largely brand-agnostic, but that’s about to change as the Johnson & Johnson vaccine rolls out.

The vaccine has been hailed as a game changer. It requires only a single dose rather than two doses spaced weeks apart, and it does not need freezer storage, making it a natural fit for hard-to-reach rural areas and underserved communities with limited access to healthcare and storage facilities.

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