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What you need to know about coronavirus vaccine booster shots and mixing brands

Vaccine Incentives Washington
Posted at 6:36 AM, Jun 04, 2021
and last updated 2021-06-07 12:58:14-04

After much debate about coronavirus vaccine brands, what happens if and when we need a booster shot to keep our defenses up?

ABC15 Health Insider Dr. Janice Johnston with Redirect Health spoke with us Thursday night about what to expect in the future.

Of course, we were urged to stay with one type of vaccine to complete our series. For example, if you got the first shot of Moderna, you should have received a second dose of Moderna as well rather than Pfizer.

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Now, it's still not clear exactly if and when we'll need booster shots. Johnston says experts are looking into protection against variants of the virus, how much immunity we have over time after being initially vaccinated, and more.

Studies are currently underway regarding mixing brands as a booster and if it really matters what kind of shot you get. Experts are trying to see whether there is a difference in the level of immunity you have if you only get the first series of vaccines, continue with a booster of the same type, or get a booster of a different type of vaccine.

"I think it will be really, really interesting to see what comes out of the study," Dr. Johnston said.

Dr. Johnston said some overseas studies are also being conducted and it appears that mixing different types of vaccines - mRNA and vector - could increase the short-lived post-vaccine side effects. It's not immediately clear what the results from those studies are in terms of effectiveness, safety, and protection.

Read more about how vaccines work from the Centers for Disease Control and Prevention here.

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