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By Tom Jeter, BS Pharm., R.Ph., Director of Clinical Services

Recently President Biden’s administration has recommended that all Americans should receive a third dose of their Pfizer or Moderna vaccine eight months after their second dose, starting as soon as Sept. 20. With that word, there has been much concern that something is wrong, but Albert Shaw, MD, Ph.D., Yale Medicine infectious diseases expert stated “…we have to remember that we are learning about this as we go.” Booster shots are not a new idea and have been used since vaccines were first developed. This is as it is, with the COVID-19 vaccine which means a third dose of vaccine from Pfizer or Moderna or a second dose of Johnson & Johnson are to be expected.

To gain more understanding let’s answer a few questions.

What is a booster?

The easiest way to answer this is that it’s just another dose of the same vaccine you received. This is found valuable when prolonging protective immunity is needed, particularly if there is evidence that protection is waning after a period. Most children receive routine vaccinations, including boosters, for illnesses such as chickenpox, tetanus, diphtheria, mumps, measles, and rubella to name a few. These vaccine series of shots are recommended because it’s needed to get longer protective immunity. So it is with the COVID-19 vaccine.

Why might we need a booster for COVID-19?

While a booster may represent the exact replica of the initial vaccine, it many times can be tweaked. With COVID-19, this is important because the vaccine could be tailored to target particular variants of the virus. Dr. Shaw stated recently in an article, “The current vaccines are still effective against the variants we are now seeing, particularly for protecting against a serious illness that would require hospitalization or cause death. But if the virus evolves further and there is a worse variant, the vaccine could be modified.” He also noted that One of the great things about the mRNA technology, which the Pfizer and Moderna vaccines use, is that it’s easy to change them up to match variants, and they can be quickly produced at scale.

How will we know if we need a booster?

It is normal for virus-fighting antibodies to be less effective over a period of time. Researchers have been monitoring antibody levels in the blood as one way to measuring vaccine efficacy and found that protection remains high for six months after the second shot of a Pfizer or Moderna vaccine.

Should a booster shot only be for certain people?

When COVID-19 vaccines first became available, they were first offered to the most vulnerable, including older adults. People who are immunocompromised have also been given priority, which may explain why the FDA recently approved a third dose of Pfizer’s and Moderna’s vaccines in that population.

Could you mix and match vaccines in a booster?

In Europe, the mixing of two different types of vaccine, i.e. Pfizer followed by Moderna, has been shown to be effective but the current public health recommendations are that people should stick with one type of vaccine for all doses. The National Institutes of Health is sponsoring a study that is ongoing evaluating this right now and will hopefully have the answer soon.

Gayco is working on behalf of our partners to make sure you have the information you need to make informed decisions. Please let our Pharmacy or Consultant Staff know if there is anything we can do to help.