COVID Vaccine Booster Shots Are Coming — Here’s What To Know

Photo: Ted S Warren/AP/Shutterstock.
Jennifer Haller
Yesterday, President Joe Biden announced that every adult in the U.S. will be eligible to get vaccinated by April 19, a full two weeks ahead of his original deadline. Over 63 million Americans are fully vaccinated, and more than 108 million have received at least one dose, a total that comprises over a third of America’s population. With herd immunity now being an attainable goal, experts are already looking ahead: Vaccine makers have begun to turn their attention to COVID vaccine booster shots.
Booster shots are additional doses of vaccines, that “are given either to pump up decreasing immunity or to fight against a new variant,” explains Jill Grimes, MD, a family physician based in Texas. Not every vaccination requires a booster, she says: Tetanus vaccines require a booster every 10 years to build immunity toward the illness, while people typically only need one series of measles shots in childhood. “The flu vaccine, however, must be boosted every year, not because our immunity from the previous year is fading out, but because the virus is mutating and changing enough that last year’s protection no longer works,” Dr. Grimes says. “COVID virus acts more like the flu virus, as we are seeing new variants emerge.”
As of now, it’s unclear when exactly we’d need to start getting boosters; experts are still determining how long the current vaccines will offer adequate immunity against COVID-19. The results of a study released this week showed that the Moderna vaccine continued to offer protection six months after the second dose. “Most scientists expect that immunity will extend at least to one year,” Dr. Grimes says. She notes that right now, the current vaccines are also seemingly effective enough against the emerging new variants. “But if we start seeing fully immunized people getting significant disease from newer variants, then yes, a booster shot would be developed targeting that variant,” she says. “Frankly, that’s the beauty of the mRNA vaccines, because they can be easily modified!”
But if the pandemic taught us anything, it’s that there’s value in acting early. Pfizer, Moderna, and Johnson & Johnson have all indicated that they’re looking into creating booster doses of their vaccines. Dr. Grimes says that, at first, people would probably be encouraged to get a booster of whatever vaccine they first received (if you get the Moderna shot, you’d get a Moderna booster). But, she adds, “At some point in the future, I would not be surprised if it’s okay to ‘mix and match.’
Over a year ago, Refinery29 spoke to Jennifer Haller, the women who received one of the very first doses of a COVID-19 vaccine in the U.S., the then-unapproved Moderna vaccine. A month ago, Haller agreed to re-enroll in the trial to receive a booster shot. She got back on the phone with Refinery29 to update us on her experience. 
Refinery29: So you got the booster shot! What was that like?
Jennifer Haller: "I got a booster shot four weeks ago. They contacted me at the end of February to say that they were offering a booster shot for phase 1 trial participants. And if we wanted to accept, that would re-enroll us into the study for another 12 months. The goal is to get through really early indicators of how this booster shot might work, and what kind of efficacy they have. 
"It was an easy decision for me. For one, I wanted to get the booster to improve my own safety. But more importantly, I wanted to be part of the study, which is going to allow us to get some early indication about how we might administer boosters to others." 
Refinery29: Did you experience any side effects from the booster? How did it compare to the actual vaccine?
"The phase 1 trial that I was in is all about testing safety in humans, so they start with a small dose. I had 25 microgram doses of the vaccine. The regular dose ended up being 100 micrograms. But this booster dose was 100 micrograms. I did experience side effects, which was exciting to me — it means my body knew what to do or how to build up a defense! It wasn’t too bad. The next day, my arm was very sore and I had a little bit of nausea and a temperature with chills. But that resolved within a few hours."
What comes next?
"The process is similar to what I did before: For the week following the booster I tracked my symptoms or any side effects. Then I returned one week later and two weeks later for blood draws; tomorrow is my four week post blood draw. And then I think there will be three-month, six-month, and 12-month checkups."
We first spoke over a year ago now, right after you received the first dose of the then-unapproved Moderna vaccine. Back then, everything was so uncertain and scary. What's life been like more recently?
"Two weeks ago I was able to see my parents for the first time. They also had their first and second shots, and it was two weeks after my booster, so we were all fully vaccinated and felt comfortable. It was really wild to be able to walk into their house without a mask on, and to sit down and have dinner. It had been over a year.
"About a month ago, I was contacted by a large Facebook Group of participants of the COVID-19 vaccine trials. They tracked me down and invited me to join the group, and I received a really beautiful, overwhelming welcome from people who said that I inspired them to participate in the trial. It’s a real acknowledgement of the power of leading by example. But also of the exponential effect that my one act had on inspiring others to join the trial; and their action likely inspired others as well.  It’s a beautiful thing to experience that exponential growth from one small act."

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