We now know that at least two of the leading coronavirus vaccine candidates appear to be highly effective. But there are several important things that we don't yet know about the COVID-19 vaccines. In this Motley Fool Live video recorded on Nov. 16, 2020, Healthcare and Cannabis Bureau Chief Corinne Cardina and Fool.com writer Keith Speights discuss some of these key unanswered questions.

Corinne Cardina: We will be looking at the raw data for these interim results that have come out from Moderna (NASDAQ:MRNA) and from Pfizer (NYSE:PFE) and BioNTech (NASDAQ:BNTX). When that raw data becomes available, Keith, is there anything specific you are going to be looking for to help figure out what happens next?

Keith Speights: Yeah. There really are two things that I will personally be looking for in that raw data. One is how effective the vaccine is in the different age groups. Some vaccines are going to be more effective for younger people versus older people or vice versa. That could be important in terms of just the market opportunity for whatever vaccine it might be.

The other thing I would be looking for is the durability. How long the vaccines provide protection against infection by the coronavirus. That's going to be important. Because if you have a vaccine that provides protection for a lot longer period of time than some of the other vaccines, then that vaccine could enjoy water spread market adoption.

Corinne Cardina: Absolutely. We'll be looking to find out more about immunity length as well, not just for those who are vaccinated. but those who have been infected and have recovered. That will be important to know as well.

Corinne Cardina: It is amazing. Zooming out a little bit, we don't have long-term data for these vaccines yet. That is something that obviously has to come with time. So what are you going to be looking for as the vaccination is rolled out and more data is collected in the larger population segment? Are there any big questions that still need to be answered?

Keith Speights: Well, I think one of the obvious things is just to make sure there are no other safety concerns. So far things are looking good for these vaccines, but I think everyone will want to keep their eye on safety issues that might emerge with the larger number of participants in the studies.

Then some of the other things that we already mentioned, Corinne, things like how long the vaccines provide immunity. If it's only four months, then that's not great, right? You have to be receiving the vaccine three times a year, and I don't think anybody wants that. If it's a year or close to a year, that would be wonderful, that will be great news. Those are the things I'm really looking for.

Corinne Cardina: Definitely. If that is the case, if it is a year, will that mean people need to get vaccinated seasonally every year like with the flu shot?

Keith Speights: It's too early to know for sure, but I know a lot of scientists are speculating that that could be the case. That we could need to be vaccinated at least once a year on a going-forward basis. Now, again, it's a little bit too early to see how this thing plays out, but I think that's a reasonable expectation.

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