If you’ve been unsure whether you should or could get a booster shot – depending on your age, health or workplace status and the brand of COVID-19 vaccine you originally received – you’re not alone. The science and federal recommendations surrounding booster shots have been challenging to parse and keep up with over the past couple of months, to say the least.

But now that the Centers for Disease Control and Prevention has signed off on booster shots for certain Americans for all three of the COVID-19 vaccines available in the U.S. and has given the green light to a mix-and-match vaccine approach, it will become easier and less confusing for eligible Americans to get their booster shots.

Many people, though, still have questions about the need for boosters and wonder: How does the immune response to vaccines shift over time, and what happens when the immune system receives an added “boost” of protection against COVID-19?

Glenn Rapsinski, an infectious disease expert at University of Pittsburgh Health Sciences, helps bring clarity to these questions. Rapsinski explains the difference between the body’s initial immune response to a vaccine, which activates and mobilizes the immune system against a perceived threat, and the secondary responses that occur when the body receives a booster shot. He also discusses some of the latest research on the mix-and-match vaccine approach.

Also today:

Amanda Mascarelli

Senior Health and Medicine Editor

Discuss with your doctor whether or not you need a booster – and if so, which vaccine will work best for you. Justin Sullivan/Getty Images News via Getty Images

An infectious disease expert explains new federal rules on ‘mix-and-match’ vaccine booster shots

Glenn J. Rapsinski, University of Pittsburgh Health Sciences

As boosters are authorized for all three COVID-19 shots available in the US, the ability to swap out vaccine types looks to be a boon to the immune system.

Environment + Energy

Politics + Society

  • Girls learn early that they don’t have much of a place in politics

    Mirya Holman, Tulane University; Angela L. Bos, The College of Wooster; J Celeste Lay, Tulane University; Jill S. Greenlee, Brandeis University; Zoe M. Oxley, Union College

    As young children learn about politics and political figures, they internalize the idea that politics is a man’s world, which ultimately means political representation is heavily skewed toward men.

Arts + Culture


Health + Medicine

  • What causes ADHD and can it be cured?

    Gregory Fabiano, Florida International University

    Even when the condition lasts a lifetime, there are behavioral treatments and prescription drugs that make it easier for people with attention-deficit hyperactivity disorder to thrive.

Ethics + Religion

Science + Technology

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