ATLANTA — Federal authorities are on the way to authorizing booster shots for most Americans. Here are answers to some questions.

Q: Are boosters needed because the vaccines aren’t working?

A: No. Ongoing tracking of cases show all three vaccines are working well to prevent serious illness or death, even when tested against the Delta variant. However, the Pfizer-BioNTech and Moderna vaccines show a gradually waning protection, and the single-shot Johnson & Johnson/Janssen vaccine has never shown protection as robust as the other two brands. With an additional dose, all three vaccines show a boost in protection.

Q: Am I still considered “fully vaccinated” if I don’t get a booster shot?

A: Yes. Everyone is still considered fully vaccinated two weeks after their second dose in a two-shot series, such as the Pfizer or Moderna vaccines, or two weeks after a single-dose vaccine, such as the J&J/Janssen vaccine.

Q: So who needs a booster?

A: Federal authorities set out the rules when they authorized a booster shot for the Pfizer vaccine. There are two levels: the folks who “may” get a booster if they really want one; and those who “should” get a booster.

Start with the should: the Centers for Disease Control and prevention wants these groups to get a booster. They are:

  • Anyone 65 years of age or older
  • Anyone living or working in a long-term care facility
  • Anyone 50 or older who has an underlying medical condition.

Some others “may” get a booster, but they should weigh the pros and cons so as not to waste a dose if they don’t really need it. Those who may get a booster are:

  • Anyone 18 to 49 years old who has an underlying medical condition
  • People 18 to 64 who are at increased risk “because of occupational or institutional setting.”

Q: What occupations are considered high risk?

A: According to the CDC, high risk jobs include:

  • First responders such as health care workers, firefighters and police
  • Education staff such as teachers and daycare workers
  • Food and agriculture workers
  • Manufacturing workers
  • Corrections workers
  • U.S. Postal Service workers
  • Public transit workers
  • Grocery store workers

Q: What’s the difference between the three vaccines?

A: Both the Pfizer and the Moderna vaccines are considered “messenger RNA” shots, which means they teach the body to produce a protein that mimics the coronavirus, triggering an immune response.

The J&J vaccine uses a weakened cold virus modified to carry genetic information about the new coronavirus. While the mechanisms are different, both types of vaccine train the body’s immune system to recognize the new coronavirus and fight it.

Q: Should I take a booster from a different manufacturer than my first shots?

A: The issue of mixing and matching initial vaccines with a booster by a different manufacturer was discussed by the FDA’s advisory committee, but the committee didn’t vote to take an official position. It’s possible the CDC could take up the issue later.

Q: Wait a minute. I thought some people originally vaccinated with Pfizer and Moderna were already getting an additional shot. What’s going on?

A: This gets tricky; it’s all about the wording. The FDA and CDC back in August said that people with compromised immune systems who got Pfizer or Moderna should get a third shot, because they probably never built up the required immunity with their original two shots. But that third shot can come just 28 days after the original series, not six months; and it’s called a “third shot,” not a “booster.” So far, boosters are to come six months or more after the initial shots.

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