COVID-19 Booster: Who is Eligible and Why Do I Need One?

On September 22, the CDC and FDA approved the Pfizer COVID-19 booster shot in individuals who are now six months out from their second dose and meet certain criteria.

Individuals who meet the criteria to get the booster (must have gotten the Pfizer vaccine, ages 65 and older, those with underlying medical conditions, educators, and healthcare workers) are now encouraged to get the shot. Those who received Moderna or Johnson & Johnson vaccines are not eligible to receive a Pfizer booster dose at this time.

The U.S. has purchased a combined 1 billion doses from Pfizer and Moderna. For now, booster shots are being advised for the mRNA vaccines only. Health officials say a separate booster for individuals who received a Johnson & Johnson one-dose vaccine is expected soon.

The University Health Center began administering Pfizer boosters on Monday, September 27. Anyone who meets the criteria outlined by the CDC may now sign up to receive the shot.

So why should we get the booster shot? Are the vaccines failing?

The answer is simple—the vaccines are not failing, and boosters are given to increase immunity.

The CDC calls this “waning immunity”—when protection given from a vaccine has decreased over time.

Getting a booster shot is also not something unusual—tetanus, measles, and varicella vaccines all require boosters. Flu shots are also recommended every year.

“The data consistently demonstrate a reduction of vaccine effectiveness against infection over time,” the CDC’s director, Dr. Rochelle Walensky, said at a White House briefing.

“We know that even highly effective vaccines become less effective over time,” U.S. Surgeon General Vivek Murthy said at the same briefing.

Fully vaccinated individuals are still very well protected from getting seriously ill from COVID-19, and Dr. Ken Rosenthal, professor of immunology at the Augusta University/University of Georgia Medical Partnership, said waning immunity is commonplace.

“Booster vaccines reawaken and amplify the immune response to increase levels of protection,” said Rosenthal. “With time, the antibody levels decrease. This is natural and a good thing, but the immune memory remains. As with other vaccines, the strength of the response and how long it is effective is different for every individual.”

Rosenthal said the Delta variant has made it increasingly important to get vaccinated and get the booster.

“With the Delta variant dominating the environment, it is important to have as strong of an antiviral immune response as possible,” said Rosenthal. “The Delta variant that has become the dominant strain of virus results from naturally occurring mutation. Delta poses more of a challenge for the immune response, and the immune response of some vaccinated people may not be up to the challenge, and they will get COVID. Fortunately, usually milder than those who are unvaccinated.”

Even though positive cases are remaining below peak numbers, Rosenthal encourages getting vaccinated.

“The vaccines have proven to be safe and effective in millions of people,” said Rosenthal. “Yes, they do cause some side effects in some people, but some of the side effects are due to the immune response elicited by the previous vaccination and causes raised warm, painful skin at the site of injection and may cause a short-term fever, tiredness, and headache. Lasting problems are very rare.”

Rosenthal also stresses the vaccine does not guarantee that you will not contract COVID, but highly lessens the chance of becoming severely ill and possibly dying.

“The COVID-19 vaccines activate immune responses that protect the recipient from getting seriously ill,” said Rosenthal. “The available vaccines from Pfizer, Moderna and Johnson and Johnson activate strong protections that prevent the virus from progressing into our lungs and through our bodies. This is meant to limit infection to being asymptomatic or at worst, mild cold like symptoms.”

As of September 28, only 45% of Georgia’s population have been fully vaccinated. Athens-Clarke County’s population is currently at 44% fully vaccinated.

Ninety percent of COVID patients currently at St. Mary’s Healthcare System in Athens are unvaccinated.

“Hospital ICUs are filling up again with COVID-19 infected people, almost all of whom are unvaccinated,” said Rosenthal. “Not getting the vaccine or the booster increases your risk for serious COVID disease and increases the chances that you will need hospitalization. This is very expensive and takes up ICU beds preventing individuals with other life-threatening diseases from hospitalization. Not getting the vaccine or the booster also increases your risk of becoming a spreader to others, especially to young children who are not yet eligible to receive the vaccine.”

To schedule your booster shot at the UGA Health Center, visit You must bring your vaccination card to your appointment.

To see if you qualify for your COVID booster, visit

For more information about attending the Medical College of Georgia at the Medical Partnership campus

Learn More Apply Now