Many states have started administering booster shots of Pfizer-BioNTech's Covid-19 vaccine following FDA and CDC recommendations last week—but many health officials say eligibility confusion and the exclusion of other vaccine recipients has complicated the initial booster shot rollout.

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Health officials battle confusion amid booster rollout

FDA and CDC last week recommended booster shots of the Pfizer-BioNTech Covid-19 vaccine for certain individuals. Under the agencies' recommendations, Pfizer-BioNTech recipients who are 65 or older; nursing home residents; and people over 50 with underlying medical conditions are eligible to receive a third dose of the vaccine six months after their second dose. In addition, people ages 18 to 49 with underlying medical conditions, as well as those whose jobs put them at a higher risk of coronavirus infection are eligible to receive a third dose.

According to the New York Times, state health officials have already established campaigns to provide booster shots of the Pfizer-BioNTech vaccine to eligible individuals. For example, pharmacies in West Virginia last week sent staff to nursing homes to administer booster shots to residents. And in Vermont, health officials on Friday opened appointments for booster shots to people ages 80 and older, with appointments for other eligible individuals opening this week.

However, several state health officials have expressed confusion about who exactly qualifies for a booster dose, leading to challenges as they implement their campaigns for the additional doses.

"Those of us overseeing vaccine rollouts don't have a clear idea of what to do,” Clay Marsh, West Virginia's Covid-19 czar, said.

In particular, many health officials have sought clarity from CDC on which underlying medical conditions or professions meet eligibility criteria for booster doses. So far, neither FDA nor CDC have defined who qualifies as a "high risk worker" and is eligible for a booster dose, according to The Hill.

"Who's at high risk? I had to look it up. Is it firemen? I don't know," David Peterman, CEO of Primary Health Medical Group in Idaho, said. "This is so confusing to the public and creates mistrust. And we can't have that right now. Right now, we need the public to say, 'Let's get vaccinated.' And for those that need boosters, we need to say that 'This is safe, and this is what we need to do.'"

However, even with limitations on eligibility, some doctors are being forced to determine which conditions or jobs qualify individuals for boosters, and other adults who want a booster shot of the Pfizer-BioNTech vaccine will be able to get one by self-attesting they are part of one of the eligible groups, the Washington Post reports. Currently, 70% of vaccine doses are being administered at pharmacies, which don't require additional documentation to prove eligibility for booster shots.

Where do recipients of other vaccines currently stand?

According to health officials, adding to the confusion is the fact that recipients of Moderna's and Johnson & Johnson's (J&J) Covid-19 vaccines are not currently eligible for booster doses—leaving many potentially vulnerable people without access to extra doses.

Mark Levine, Vermont's top health official, said many teachers in the state received the J&J vaccine, and in West Virginia, residents in more isolated nursing homes received the Moderna vaccine, the Times reports. Anne Zink, Alaska's top health official, also said many rural communities in the state received the Moderna vaccine.

Moderna has applied for FDA authorization of its booster shots, but J&J has not yet submitted an application to FDA for booster shots of its vaccine. However, J&J last week announced data showing its vaccine is more effective when a second dose is administered two months after the initial shot, suggesting a booster shot may be beneficial.

"The fact that we won't have recommendations for people who received Moderna and J&J because the companies haven't gotten the data in ...  that's gonna cause heartburn all over the place," Richard Besser, former acting CDC director and current president and CEO of the Robert Wood Johnson Foundation, said.

"People didn't have a choice of what vaccine they got," he said. "They're all effective, but only one of them can get boosted right now."

However, members of CDC's Advisory Committee on Immunization Practices (ACIP) last week discussed mixing vaccine doses for booster shots. Specifically, Wilbur Chen, an ACIP member and physician from University of Maryland said boosters should be recommended "agnostic of primary series"—suggesting that recipients of other Covid-19 vaccines may be eligible for booster does of the Pfizer-BioNTech vaccine in the future.

The plan for booster shots going forward

At a White House briefing on Friday, Surgeon General Vivek Murthy said it is "extremely important" that people receive clarity on the booster recommendations. He added that federal officials have been working with state and local health officials on the roll out of boosters to different populations over the last month.

"We'll continue to get information out through a variety of means to make sure people know how to put these recommendations into effect," Murthy said.

Separately, CDC Director Rochelle Walensky said the agency doesn't "necessarily have an answer" yet on whether annual booster shots of the Covid-19 vaccine will be required.

"I want to emphasize that our goal right now is to stay ahead of the virus," she said. "We want to boost now so we don't end up in a vulnerable place."

Walensky added that despite the current focus on booster shots, CDC's most important goal is to vaccinate those who are still unvaccinated, since they are the most vulnerable population.

"I want to be clear: we will not boost our way out of this pandemic," she said. (Weixel, The Hill, 9/26; Christ, Modern Healthcare, 9/24; Firozi et al., Washington Post, 9/27; Weiland et al., New York Times, 9/24; McGinley/Sun, Washington Post, 9/24; Walker, MedPage Today, 9/24; Choi, The Hill, 9/26; Wolf et al., Washington Post, 9/25)