Two shots of the J&J vaccine offer 94% protection from COVID-19, the company announced this week.
As many Pfizer recipients start getting boosters, J&J recipients have been left wondering what's next for them.
Here's what health officials have said so far.
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The 14.9 million Americans who received the Johnson & Johnson vaccine may have a bone to pick with the Centers for Disease Control and Prevention.
"I count myself among those few and now not-so-proud," New York Magazine's Benjamin Hart wrote in a piece on Thursday, with the simple headline: "Johnson & Johnson & Regret."
The shot, a convenient one-and-done single dose, suffered a kind of fall from grace during its rollout: A factory mix-up led vaccine ingredients to be improperly mixed, then the CDC issued a pause on the vaccine altogether while they examined the risk of an an extremely rare blood clot condition. Regulators later added a warning label for women under 50.
Most recently, there's been radio silence from the CDC and Food and Drug Administration about the possibility of a J&J booster shot, though a third Pfizer dose was authorized for many groups this week, and the same is expected of Moderna in the near future. Both were previously authorized for immunocompromised people, but even that hasn't been true for J&J.
"Despite being in real need of some direction, it has often felt as if we've been cast out of the pandemic narrative altogether - like we're the Generation X of vaccine recipients," Hart wrote.
To shed some light for J&Jers, here's what health officials have suggested so far.
Will I need a second shot?
"For people who received the Johnson & Johnson vaccine, we anticipate vaccine boosters will likely be needed," Dr. Vivek Murthy, the US Surgeon General, said during a White House briefing last month. "The J&J vaccine was not administered in the US until March of 2021, and we expect more data on J&J in the coming weeks. With those data in hand, we will keep the public informed with a timely plan for J&J booster shots."
That information arrived on Tuesday, when J&J released results from its clinical trial showing that two doses of its vaccine led to 94% protection against mild to severe COVID-19, up from the 74% efficacy found in the trial of its single shot.
While the data has not yet been peer reviewed, it puts a two-shot J&J vaccine on par with the mRNA vaccines offered by Pfizer and Moderna.
So it's likely that second J&J shots are on the way, but when exactly those boosters will be recommended by the CDC and authorized by the FDA is not yet clear.
Can I get an mRNA booster while the CDC figures things out with J&J?
You probably shouldn't, but check with your doctor.
So far, all vaccine recipients have been advised to stick with the same shot when they get a booster, since there isn't yet trial data about mixing and matching.
But health officials in San Francisco went rogue in August, telling J&Jers they would give them mRNA boosters if their doctors recommended it.
"If people talk to their health care provider and say, 'I'd really like to have an mRNA shot in addition to the Johnson & Johnson shot that I got,' we will accommodate that," said Dr. Grant Colfax, the director of San Francisco's public health department, according to CBS' San Francisco affiliate.
The CDC estimates that 1 million Americans got an unauthorized COVID-19 booster prior to the recent recommendations, ABC News reported. It's unclear how many of those were under the recommendation of a doctor.
"We are strongly recommending that people do not do that," Dr. Anthony Fauci said of those unauthorized booster shots in an interview with CNN on Sunday,
"We recommend that people wait until you get to the point where you fall into the category where it's recommended," Fauci added.
Still, he recognized that people simply want protect themselves against COVID-19 to the greatest extent possible.
"That's human nature. Not much you can do about that," Fauci said.