Some Americans receiving unapproved COVID-19 booster shots

With the Delta variant quickly spreading locally, many are wondering if a booster would give them more immunity.

The FDA is expected to announce authorizing the booster shot for some people who are immunocompromised.

The booster shot is the third shot of the current two-dose Pfizer and Moderna vaccines. The CDC estimates that more than 1 million people have already received the unauthorized third booster shot.

"Just going to a place to get vaccinated and not telling the place that they have already received their two vaccines. That’s how they are getting their 3rd dose," said Dr. Catherine Troisi, an infectious disease epidemiologist at UTHealth School of Public Health.

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She says the vaccine hasn’t been studied long enough to know if a booster is needed.

"Antibody levels do decrease with time. That happens with any vaccine, but there is another part of your immune system that is harder to measure. We do not routinely measure it, but it is very important in protecting you against disease, so we really aren’t sure if the overall boosters are going to be necessary."

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The concern is for those with compromised immune systems. A recent study by Johns Hopkins researchers found that vaccinated immunocompromised people are 485 times more likely to end up in the hospital or die from Covid-19 compared to the general population that is vaccinated.

"If we start seeing a lot of breakthrough infections with serious consequences, like hospitalization or death, then a booster would definitely be recommended."

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According to a meeting agenda posted by the CDC, vaccine advisors will meet on Friday to discuss the booster shots for immunocompromised people. When it comes to all vaccinated Americans, the Biden administration is expected to lay out a Covid-19 vaccine booster strategy next month.