By her own account, Elizabeth Calder has little reason to fear her life would be in danger if she caught COVID-19.
The 33-year-old graduate student in Boston has no health problems. She ran a half marathon this summer with little training and is, in her words, “super fit.” She received Johnson & Johnson’s one-shot coronavirus vaccine in April and obeys mask-wearing mandates.
But after reading about worrisome breakthrough infections in the spring and wrestling with her conscience, Calder went to the Hynes Convention Center in May and June and got two Pfizer-BioNTech shots to boost her immunity even though she was not eligible under federal guidelines. Remote learning was unbearable early in the pandemic, she explained, and she was desperate to avoid testing positive with an infection that would force her to quarantine at home.
“I just showed up [at the Hynes] and gave them my name and address, and they told me to roll up my sleeve,” said Calder, who asked the Globe not to identify her university because she didn’t want her actions to cast it in a bad light. “Anything I can do to avoid going to school on Zoom is something I’d go to great lengths to do.”
No one at the convention center asked Calder whether she was already vaccinated, she said, and she didn’t volunteer anything. The state Department of Public Health, which ran the vaccination site, said people attest to their eligibility throughout the vaccine rollout.
Calder is hardly the only person getting unsanctioned shots. While an estimated 70 million Americans are eligible for COVID vaccines but remain unvaccinated to the dismay of public health officials, many fully vaccinated people, including some in Massachusetts, are flouting guidelines and getting extra shots.
Their reasons range from fears of getting a second debilitating case of COVID to uncertainty about when they will become eligible for an additional shot, to simply wanting the $100 Walmart gift card one state offered to entice reluctant people to get primary shots.
No one knows exactly how many Americans have received unauthorized extra shots, but it appears to be a lot. The US Centers for Disease Control and Prevention estimated it was over 1.1 million people in an Aug. 13 report, which collected data before regulators had cleared extra doses.
Kristen Nordlund, a CDC spokeswoman, said Wednesday the agency hasn’t updated the numbers and has no way of knowing who is disregarding the guidelines now; people can lie by saying they are immunocompromised or that they haven’t been vaccinated when they go to a pharmacy or clinic.
“There are no individual penalties for quote-unquote jumping the line,” she said.
As of Friday more than 6.7 million people in the US have received extra doses, including more than 167,000 in Massachusetts, according to federal and state health officials. The US Food and Drug Administration last month cleared a third Pfizer shot for people who had received that vaccine and were 65 and older or had medical conditions, occupations, or living situations that made them more likely to get seriously ill from COVID. An FDA advisory committee is scheduled to meet Thursday and Friday to discuss authorizing additional shots from Moderna and J&J.
Several people interviewed by the Globe said they didn’t arrive at their decisions lightly, and some didn’t want their full names published because of embarrassment.
David Fournier, a retired chief financial officer for a media firm, said he had some misgivings but got a third Pfizer shot at a CVS in Burlington on Sept. 13 because he was attending a large party several weeks later and has a friend who is immunocompromised. He wondered whether it was ethical to jump the line, but health care workers he knows told him not to fret.
“They said just go and get the shot because most of all they want to get needles in people’s arms,” he said. At the time, third shots of the Pfizer and Moderna vaccines were authorized only for immunocompromised people. Fournier, 65, didn’t qualify under that provision, but he became eligible several days after he got his third shot, when the additional Pfizer booster was cleared for people 65 and older.
CVS requires customers to attest they are eligible for a vaccine but does not require documentation, according to Mike DeAngelis, a CVS Health spokesman, who says the firm follows federal guidance.
Dr. Arthur Caplan, a professor of bioethics at the NYU Langone hospital system in New York, said he’s surprised more people haven’t finagled unauthorized shots, considering that the government imposes no penalties. “You basically have suggestions, not rules,” he said.
It’s also hard to blame people for gaming the system, Caplan went on, given recent studies indicating that immunity from the vaccines may wane over time. Indeed, a growing body of evidence suggests that the two-dose messenger RNA vaccines from Pfizer and Moderna actually require three shots to provide durable protection and that the one-shot adenovirus vaccine from J&J actually requires two.
“If you call it a booster, it sounds like you’re lining up to get dessert after a good meal,” Caplan said. “If you call it a three-shot vaccine, you’re finishing your dinner.”
Nonetheless, some vaccine experts say it’s still unclear whether it’s safe or wise for healthy people to seek out extra shots, including doses of a different vaccine from what they first received. While a number of scientists believe that mixing and matching shots might broaden the immune response, researchers don’t know for sure yet.
“The data are not in, but there’s no reason to believe there will be a safety issue,” said Dr. Lindsey Baden, an infectious disease expert at Brigham and Women’s Hospital who helped lead a large nationwide trial of the Moderna vaccine last year. “What’s difficult in this business is that everything changes so fast that the way we think of approaching the problem today may be different next week.”
One retired postal worker from Boston said he got a Pfizer shot at a vaccination clinic outside City Hall in August, four months after he received his second Moderna shot. The 65-year-old retiree, who asked to be identified only by his first name, Robert, said he didn’t know when regulators would authorize a third shot for Moderna recipients and wanted to feel safe when he visited relatives in New Hampshire during the holiday season. He brought no identification, gave a fake name, and easily got the shot, he said.
“The problem is people who aren’t getting vaccinated, not people who are getting overvaxxed,” he said. “I thought, ‘I’ll take another shot, give it to me.’”
Other fully vaccinated people said they had survived one bout with COVID before they got inoculated, knew how bad it was, and didn’t want to take the chance of getting a breakthrough infection.
“That was the sickest I’ve ever been,” said a 46-year-old high school teacher in North Andover whose family came down with COVID last December. The teacher, who asked that only her first name, Laura, be used, said she was so fearful of getting sick again that she went to a CVS in Billerica earlier in October and got a third Pfizer shot. When she registered online, she said she was eligible as a teacher but didn’t add that she was also out on leave until January.
A Colorado man, Mark Bliton, who received a J&J shot in March, said he got a Pfizer shot in early August, but not because of health concerns. It was dollars and cents.
Bliton, 54, whose niece studies business at Suffolk University, said his wife is a registered nurse and told him that fully vaccinated people were inevitably going to need additional shots. His state was offering $100 Walmart gift cards to persuade people to get vaccinated, so when a mobile vaccination clinic came near his home in suburban Denver, he figured it was too good to pass up.
“I know this sounds terrible,” said Bliton, a former tech employee who now owns and manages apartments. “It was a feeling that they’re going to make us do it anyway, and these gift card programs aren’t going to be around forever, so I might as well do it.”
Jonathan Saltzman can be reached at jonathan.saltzman@globe.com.