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The Food and Drug Administration approved the booster shot on Nov. 29 for all individuals 18 and older, at least six months after their completion of the initial two-dose sequence of either Pfizer-BioNTech or Moderna COVID-19 vaccines, or at least two months after the Johnson and Johnson (Janssen) vaccine. But what led to this authorization, and why is the booster shot important?

How the FDA makes decisions

Centers for Disease Control and Prevention recommendations are not always followed by FDA approval. However, the CDC recommended the booster shot in September of this year. The FDA’s approval came promptly in October after the currently available data was reviewed and deemed adequate enough for an amendment to the Emergency Use Authorization

Notably, the October approval was set for individuals 65 and older or between the ages of 18 and 64 only if the individual is at high risk of exposure to Sars-CoV-2. The November amendment to the October approval expanded the eligible demographic to include all individuals 18 or older regardless of risk or exposure to COVID-19. 

Dr. Arnold Monto, University of Michigan professor of epidemiology at the School of Public Health, sits on the Vaccines and Related Biological Products Advisory Committee for the FDA, where he and his colleagues evaluate new data and give input on the appropriate use of vaccines and other biological products. He said recommendations and authorizations from the FDA are arduous and quite difficult to come by. 

Monto also said the reason their first authorization excluded the younger demographic was because the VRBPAC uses risk-benefit analysis in their eight-hour meetings to make most of their decisions.

“The committee felt that there was not yet evidence that (the booster) was necessary in younger individuals who were not at high risk because there could be other problems occurring,” Monto said. “And the problem that has gotten in the way of a broader author reception is the low frequency of myocarditis … so, it gets very complicated.”

With new research finding a very small risk of myocarditis, or inflammation of the heart wall’s middle layer, in young adult men who take the vaccine, the risk-benefit analysis led them to make a decision that would ultimately decrease the amount of people exposed to such a risk until further data could be collected. 

The data behind the decision

In an email to The Michigan Daily, Dr. Emily Martin, associate professor of epidemiology at the School of Public Health, gave more insight on how the FDA made the decision to expand the eligible age for the booster.

“The FDA evaluates how effective the shot is and balances that against any risks,” Martin wrote. “These recommendations are evolving based on the accumulation of data about waning of immunity in certain groups, both here in the U.S. and in other countries.”

The recent challenge of assessing the vaccine’s waning in efficacy over time and a potential variant on the way put the VRBPAC in a tough spot regarding whether or not to expand the booster shot’s demographic. Ultimately, the amendment to the EUA was passed largely due to the ample supporting evidence noting the vaccine’s waning immunity. 

Dr. Pamela Rockwell, professor of Family Medicine at the University of Michigan Medical School and co-chair of the U-M Immunization Committee, said she believes the new CDC data was consequential enough to elicit such alterations to the vaccine authorization. 

“The new data is showing a decrease in the efficacy in the vaccine to the delta variant,” Rockwell said. “Now that (the delta variant is) predominant in the U.S. and so many parts of the world, I think there is enough data to verify that the current vaccines that people receive do slowly reduce in efficacy over time.”

Rockwell also said this trend of decreased vaccine effectiveness is similar to the cause of annual flu shots that are timed around surges.

“You wouldn’t want to get your flu vaccine in January knowing that the flu season doesn’t start until the fall/ or winter because you could have a less effective vaccine,” Rockwell said. “(The decrease in efficacy) does depend on the vaccine type and what you’re getting vaccinated against.”

Monto said he believes the booster shot will become continual like the flu vaccine. His analysis, published in the New England Journal of Medicine, delves into the idea that a recurring COVID-19 shot may be necessary. In Monto’s analysis of the COVID-19 booster shot, he wrote that the rise in variants is similar to the reason why we need annual flu shots.

“Given the parade of variants, their varying transmissibility, and continuing concern about antigenic changes affecting vaccine protection, I believe it should now be clear that it is not possible to eliminate this virus from the population,” Monto wrote. “We need to learn to live with these illnesses, just as we have learned to live with influenza.”

The omicron variant

Although the current vaccine effectiveness for the spread of the new omicron variant is still uncertain, the World Health Organization determined that receiving the vaccine is one of the most effective ways to minimize the potential severity of another large outbreak for the delta variant, which includes the booster shot as well. 

Monto said while the decision to make the booster shot available to everyone was not because of the omicron variant, it was quite providential that there is now time for everyone to get a booster shot before the variant reaches Michigan. 

“That was the point of the boosters in the first place, to give people more antibodies,” Monto said. “So it was very fortunate that the boosters were (made available to) everyone a couple weeks before (the movement of the omicron variant to the States).”

Your booster shot 

The CDC says that individuals can now mix and match their vaccines for the booster shot. New research suggests that neutralizing antibodies — the antibodies that fight against the replication of COVID-19 — will increase with a booster shot regardless of the original type of vaccine the individual received. 

In an interview with The Daily on Dec. 7, Robert Ernst, executive director of University Health Services, said the University will be offering booster shots to all students, faculty and staff starting this week. 

“Much of the strategy in our state has been to partner with big medical centers and retail pharmacies, so there are a lot of vaccines available in the community,” Ernst said. “We are partnering with both Walgreens and Kroger to offer a number of on-campus distribution opportunities.”

The University announced they will be administering booster shots for students before the end of the semester. You can find more information here.

The booster shot itself has common side effects of pain or redness in the area the shot was administered and tiredness, fever or chills. Engineering junior Zachary Eichenberger got his booster shot last Friday and said it was important to him that he kept everyone around him safe.

“​​I really wanted to get my shot in part to protect myself with (the omicron variant) going around but also because it means I don’t have to worry as much about spreading COVID to my family and friends,” Eichenberger said. “I did have a few symptoms afterwards, and had a pretty bad headache the next day, but other than that it was not as bad as my second shot. I was pretty much fully functional after about 24-36 hours.” 

The booster dose is not currently mandated for all students because the CDC considers an individual fully vaccinated after the completion of their initial dose sequence. However, Ernst said that vaccination and masking indoors are two of the most important strategies implemented by the University that has allowed students and staff to enjoy an almost normal semester. 

“Getting vaccinated is clearly the most effective strategy to keep yourself from both catching covid and transiting it to others,” Ernst said. “With emerging variants, it’s important to stay on top of this. It’s a way to promote a healthy campus and a health-promoting campus is one that recommends widespread vaccination as a primary strategy. It is a safe strategy to allow us to offer the Michigan experience that students want.”

Daily Staff Reporter Nadir Al-Saidi can be reached at alsaidin@umich.edu.