Your questions about booster shots answered: Who qualifies and more

Local public health agencies and hospitals began giving out third doses of the Pfizer vaccine this week to eligible residents at the highest risk of contracting severe COVID-19 and those with high occupational exposure.

Less than a week after the Centers for Disease Control approved such booster shots, readers have a lot of questions about such doses, including how they differ from third shots authorized for immunocompromised people last month. The Dayton Daily News has assembled a panel of trusted local experts, including doctors and pharmacists, to answer your questions on a regular basis. Here are answers to some of the questions we’ve received from readers related to booster shots.

Experts quoted in this article are:

  • Dr. Mamle Anim, chief medical officer for Five Rivers Health Centers.
  • Dr. Roberto Colón, chief medical officer at Premier Health’s Miami Valley Hospital.
  • Dr. Jeffrey Weinstein, patient safety officer at Kettering Health.

Q: Who should get a third shot right now?

Anim: People who are moderately to severely immunocompromised should receive an additional (third) dose of an mRNA COVID-19 vaccine (Pfizer or Moderna) at least 28 days after the two-dose series.

Currently, only qualified individuals who received the Pfizer vaccine series are approved for a booster six months after their second dose.

Individuals who are highly encouraged to get the booster:

Individuals who may choose to receive the booster:

  • People 18 to 49 who are at high risk for severe COVID-19 due to certain underlying medical conditions.
  • People 18 to 64 who are at increased risk for COVID-19 exposure and transmission because of occupational or institutional setting. Eligible occupations are first responders (health care workers, firefighters, police, congregate care staff), education staff (teachers, support staff, daycare workers), food and agriculture workers, manufacturing workers, corrections workers, U.S. Postal Service workers, public transit workers, grocery store workers. The CDC has said this list could be updated in the future.

Q: What is the difference between third shots and booster shots? And why do some people need them?

Colón: The “third shot,” which is approved for those with immune deficient conditions, is intended to be part of the initial series of vaccines. In patients with immune suppression, such as those on certain chemotherapies, the body does not mount as robust of a response to all vaccines. In these individuals, a third dose is necessary to obtain the initial level of immune protection. It is not unusual to see this adjustment for some immune deficient conditions as we already do this with flu vaccines — giving certain older adults or those with immune deficiency high dose flu vaccines to help them attain the same level of protection as others may obtain with more standard doses. The third dose may occur as early as four weeks after the second dose of Moderna or Pfizer vaccination.

Boosters, on the other hand, are intended to “boost” a weakening level of immunity, which occurs after some time. This booster dose is currently only recommended for certain adults, such as those over the age of 65, those with risk factors for severe disease, and individuals who have a high risk of exposure from their place of work or residence. This booster is only available for Pfizer vaccines and is intended to be administered six months after completing the initial vaccine series.

Credit: Submitted

Credit: Submitted

Q; Are third shots the same as other coronavirus vaccines used for first and second doses?

Weinstein: The booster dose is the same product and dose as the first two-shot series of the Pfizer vaccine. It is important to know that there is no actual difference between a booster versus a third dose.

Colón: Currently, the booster dose for the Pfizer vaccine is the same as the initial doses. In the future, it is possible that other adjustments may be made for boosters, but those changes are not currently planned.

Q: I qualify for both a third coronavirus shot and a booster shot. If I just got my third shot, how long should I wait to get my booster shot?

Anim: No one should get more than three shots at this time.

Colón: This is a very interesting situation as the third dose series and boosters were not necessarily studied together. If someone has just received a third dose as indicated, a booster would likely not be required until at least six months after the final dose was administered. It is likely more data will be available in the near future to help establish a more definitive recommendation.

Q: Can recipients of the Moderna or Johnson & Johnson vaccine get another shot?

Currently, the U.S. Federal Drug Administration and the Centers for Disease Control and Prevention recommend against mixing and matching coronavirus vaccine doses from different manufacturers. White House chief medical adviser Dr. Anthony Fauci on Tuesday said that safety and efficacy data on pairing an initial series of coronavirus vaccines from one manufacturer with boosters from another could be available within the next two weeks.

Nobody who received the Johnson & Johnson vaccine can currently receive any additional doses.

Recipients of the Moderna vaccine who are moderately to severely immunocompromised can receive a third shot as part of their initial series at least 28 days after getting their second dose.

All other recipients of the Moderna vaccine cannot get a third dose since booster shots have only been approved for the Pfizer vaccine. Approval of a booster for Moderna and J&J vaccines is expected in the coming months.

Q: I recently had COVID-19. Do I need to wait before getting the booster vaccine I qualify for? How long?

Colón: It is still recommended that individuals who recover from COVID-19 infection receive a COVID-19 vaccine, as this leads to a very high level of protection from reinfection. The recommendation is for the vaccine to be administered after recovery from the acute illness, which is typically around 10 days from onset of symptoms. For those who have more severe illness, recovery may require a longer period of time based on the symptom duration and severity.

Q: Why is the cut-off for the booster at 65? Other countries use 60. The 60-64 year old age range also seems to be a vulnerable group of older adults.

Weinstein: This decision was made by the FDA and CDC based on their review of data from the U.S. and other countries. Younger people have a more vigorous immune system and usually will generate higher antibody levels than older people. Since the levels are higher, they tend to persist in a protective range for longer periods of time.


Have questions about COVID-19, face masks, vaccines, testing, quarantining or anything else pandemic-related? Send them to jordan.laird@coxinc.com. Answers will be published regularly in print and online.

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