Millions of Americans have already received two COVID-19 vaccine shots. However, there's a possibility that a third booster dose will be needed. In this Motley Fool Live video recorded on May 17, 2021, Healthcare and Cannabis Bureau Chief Corinne Cardina and Motley Fool contributor Keith Speights discuss when we'll know if a booster shot will be required or not.

Corinne Cardina: Let's talk about the future of booster shots speaking of making a lot of money in the long run. What should investors know? What's the latest in terms of when are we going to know when we'll need more shots, whether it's a year out. Tell me about that.

Keith Speights: Dr. Fauci predicts that we'll know by the fall if a booster shot is going to be required. I think his projection is probably about right. I think sometime in the fall we will know whether or not we're going to need a booster shot or not.

Now, Pfizer (NYSE:PFE) CEO, Albert Bourla, has stated publicly that he thinks a booster shot will likely be required. There are some experts who are less certain about that. We'll see.

Pfizer and Moderna (NASDAQ:MRNA) are evaluating third booster doses. They are also evaluating in clinical studies variant-specific vaccines. Pfizer expects to have some data from its clinical studies in July, which is right around the corner. Moderna's already reported some positive results from a phase II study earlier this month, actually, for a booster dose and a variant-specific version of its vaccine so it's looking very promising for Moderna.

I wouldn't be surprised if Americans don't actually have to get the third booster shot. But I do expect we're going to require annual vaccinations with a single dose vaccine that targets variants, probably along the lines of what we see with the flu right now where we have annual vaccinations and the flu strains change from year-to-year and they modify the vaccines that are distributed each year.

Personally, I think that's probably what we're going to see. I'm not as confident that these companies are going to benefit from being able to sell third booster doses later this year or early next year.

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