After months of discussion about who would become eligible for additional doses of a COVID-19 and when, federal health officials authorized a booster shot for Pfizer vaccine recipients age 65-plus and those at high risk of contracting the virus or developing severe complications from it. (A third dose was approved for people who are immunocompromised in August.)
In its recent booster approval, federal health officials recommended some populations get a third dose, while other populations are allowed to get a shot if they choose.
That means many Minnesotans will be having to make a decision in the coming weeks and months. If that group includes you, here are some answers to frequently asked questions about the booster shot, including what it does and how to get it.
Who is currently eligible?
A few weeks ago, it seemed that pretty much everyone who was vaccinated might be eligible for an additional dose of a COVID-19 vaccine before long. But some experts opposed that policy, arguing vaccine manufacturing capacity should be used to get initial doses out to more of the world more quickly — and also because of evidence that the vaccines remain highly protective in the general population without booster doses.
Ultimately, officials settled on making a more limited scope of people eligible for additional doses, at least for now. Also: the new booster-shot eligibility only applies to people who got the Pfizer vaccine. Regulators are still looking at data regarding Moderna and Johnson & Johnson boosters.
Those recommended to get a third dose include people who received their second Pfizer dose at least six months ago and:
- Are age 65 and older
- Live in long-term care facilities
- Are age 50 to 64 and have underlying health conditions like cancer, kidney disease, heart disease, diabetes and others that potentially put them at higher risk of COVID-19 complications (listed here).
Those who are allowed to get a third dose include people who received their second Pfizer dose at least six months ago and:
- Are ages 18 through 49 and are at high-risk of COVID-19 complications because of health conditions like cancer, kidney disease, heart disease, diabetes, pregnancy and others that potentially put them at higher risk of COVID-19 complications (listed here).
- Are ages 18 through 64 and at high risk of contracting COVID-19 because of a workplace or living situation. That would include people who live in group homes, and people who are frontline medical workers, those who work in schools and child care and first responders.
Why those groups?
The rationale for a booster is different for different groups.
For people age 65 and older, data indicate a benefit to boosting the immune response of older people with an additional dose, said Dr. Amy Karger, a clinical pathologist with the University of Minnesota Medical School and M Health Fairview. Karger is leading a study that compares the response of immunocompromised and healthy people’s immune systems to COVID-19 vaccines.
An Israeli study, for example, found people age 60 and older who got a third dose of Pfizer’s vaccine were less likely to get COVID-19 or have severe cases of it if they were infected, compared to those who didn’t get a third dose.
That’s not surprising, Karger said, because of a thing called immunosenescence, or, the fact that as our immune systems age, they are less responsive than younger immune systems. “As you age, your immune system generally isn’t able to mount as much of an immune response,” Karger said. “Even with other vaccines — like the flu vaccine — we have a high-dose version for elderly patients, because we know they need more flu antigen to respond the same as a young person.”
For younger people with certain health conditions, like heart or kidney disease, diabetes or smoking, an extra dose is recommended (in the case of those 5o to 64) or allowed (in the case of younger people) because those conditions put people at higher risk of severe complications from COVID-19. That means in the rare event they do end up in the hospital, even though they’re vaccinated (0.047 percent of fully vaccinated Minnesotans have been hospitalized, per the most recent numbers), they are more likely to get sicker than people without those conditions.
For people in living or work conditions that could expose them to COVID-19 but who are otherwise healthy, an extra dose is permissible because these people are more at risk of catching the virus than others, whether that’s because they’re frontline health care workers, teachers or because they live in homeless shelters or prisons.
Karger said it’s not clear whether a third dose for an otherwise healthy person will result in more than a temporary boost in immunity. “If you give a booster, you can induce another peak [in antibodies],” she said. “But we don’t know yet for sure, when they stabilize and come back down, are they in a better place than they were after just two doses?”
For the immunocompromised, an extra dose is recommended at least 28 days after the second dose because people in this group — whether it’s because of a medical condition like advanced HIV or because of drugs like some chemotherapies, which suppress the immune system — don’t always get much of a response out of the earlier doses. Immunocompromised people who received either the Pfizer or Moderna vaccines have been eligible for boosters since August.
Researchers have found people in this group “either had no evidence of an immune response or what we would call sub-optimal response, which is not nearly the degree of antibody response that we would see in a person with a healthy immune system,” Karger said.
Some people who are immunocompromised who don’t respond ideally to the first and second shots are responding to the third, Karger said, whether that’s because of timing of the vaccines and timing of drugs they’re on, or for other reasons.
What about people not in those groups?
Experts say it’s not clear yet that boosters are needed for the general population, because we don’t know if the boost in immunity would be more than temporary for most people, and because the vaccines are still very good at preventing severe illness and hospitalization — even against the delta variant.
What is encouraging, is that in six-month post vaccine studies, immunity levels seem to be holding pretty steady and not dropping off. So if you’re relatively healthy, your immune system appears to establish a stable ability to respond to the virus, Karger said.
Do people who receive a third dose typically report symptoms afterward?
They’re not uncommon, and studies have found people’s reactions to the third Pfizer shot much like the second.
More specifically, a study by the Centers for Disease Control released this week found 79 percent reported a “local” reaction (like arm soreness or redness) after the third dose, while 74 percent reported a “systemic” reaction like fatigue or muscle soreness. For the second shot, those rates were 78 percent and 77 percent, respectively.
How do I decide whether to get a third shot if I’m among those allowed (but not recommended) to get a third dose?
Karger said to look at the booster dose guidelines and evaluate how they align with your health and level of risk. “For example, health care workers who are often around patients with COVID infection in the hospital or clinic setting. I think that, if that were me, I would absolutely be first in line to get a third dose,” Karger said.
For teachers, consider underlying risk factors — diabetes, obesity, heart disease — and things like the district’s mask policy.
Data coming out of countries that are administering third doses more widely suggest there aren’t additional risks posed by the booster.
Minnesota health officials have also recommended people talk with their doctors to assess their level of risk and whether or not a booster shot might be a good idea.
What if I didn’t get a Pfizer shot? Am I out of luck?
Not necessarily, as news on Moderna and Johnson & Johnson boosters is expected soon. “We do expect that there will be recommendations about boosters probably from Moderna within just a few weeks and Johnson & Johnson shortly after that,” Minnesota Health Commissioner Jan Malcolm said on a press call last week.
Scientists are also studying the efficacy of mixing and matching doses, Karger said, though it’s worth noting the CDC isn’t currently recommending you seek out an additional dose from a different manufacturer than your original shot or shots.
Is there concern about a shortage in boosters or the capacity to administer them?
Nope. CDC Director Dr. Rochelle Walensky has said she has no concerns about booster supply issues.
Health systems are stressed, given high COVID-19 hospitalization levels, but Malcolm said there are lots of ways to get the vaccine. “We’re quite confident the capacity exists,” Malcolm said.
MDH Infectious Disease Director Kris Ehresmann said as opposed to the urgency with which many got their first shots, Minnesotans eligible to get boosters can get them more at their convenience. “They don’t need to take it as a crisis” and get in immediately, she said.
Where can I get one?
Health care providers are busy dealing with the surge in COVID-19 cases that continues, but many are still administering shots. M Health Fairview, for example, started giving boosters on Thursday. Appointments are also readily available at many pharmacies, including but not limited to Walgreens, Thrifty White, CVS and HyVee. Local public health authorities may be offering booster clinics and the state of Minnesota is giving boosters at its Mall of America community vaccination site.