COVID-19 booster shots are being administered to fully vaccinated people considered immunocompromised, while some healthy fully vaccinated individuals may be able to get a third shot in September.
Robert Moore, of Austin, is a liver transplant recipient and received his third Moderna COVID-19 vaccine three days after the CDC approved the boosters.
"I only had mild discomfort at the injection site and a little fatigue, so for me, it was less of a problem than the other two shots," said Moore.
Experts say it is possible that people may experience strong side effects or none at all.
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"We really kind of need to keep an open mind and recognize that as we are moving forward in this emergency, that individuals may have a variety of immunological reactions after the third dose and that yet has to be fully defined so we can’t say what your percentage is of this that or the other," said Dr. Cedric Spak, Infectious Disease, Baylor University Medical Center.
"Amongst doctors, when we got our second vaccine, we would all sit and give each other high fives or fist pumps because we'd be like, 'thank goodness, the immune system works!'" said Dr. Spak.
Spak said antibody blood tests won't necessarily tell you whether you should get or skip a booster.
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The FDA warns against antibody blood tests too, saying they can't tell you if you're protected against serious illness.
The CDC says the vaccine's effectiveness does wane over time, but if you're on the fence right now getting your first shot, Dr. Spak warns that now is the time to get vaccinated.
"A lot of individuals made decisions of 'I'm not going to get the vaccine,' and now we are witnessing the error of that decision," said Spak.