What The Flu Shot's History Tells Us About Coronavirus Vaccines

Pfizer (PFE 1.26%) and its German partner BioNTech (BNTX 0.68%) reported incredible efficacy data from a phase 3 trial for their mRNA coronavirus vaccine candidate last Monday. While the 90% figure inspired much hope, investors should know this was interim data that have not yet been peer-reviewed. This week, Moderna (MRNA -2.30%) reported equally impressive results for its vaccine candidate that takes a similar approach.

The Motley Fool sat down with Dr. Jeremy Brown, author of Influenza: The Hundred-Year Hunt To Cure The Deadliest Disease In History and Director of Emergency Care Research at the National Institutes of Health. Dr. Brown shared how what we know about the flu vaccine will inform how coronavirus vaccines are understood.

Corinne Cardina: That's good news. What would you say the biggest misconception about coronavirus vaccine says it's out there that we should correct?

Dr. Jeremy Brown: Well, that's a very interesting question. I guess, the answer is we don't know a lot about coronavirus vaccine yet because we don't have one. But let me take a look at the influenza vaccine, which we've had for upwards of 50 years now. One of the problems with the influenza vaccine as I mentioned a few minutes ago, is that there are lots of different strains of influenza around. That means that each year we have to change the vaccine so that it incorporates the three or four most likely strains of influenza. That's a problem and that's one of the reasons we need to get the vaccine each and every year. Now, will this vaccine, the Pfizer vaccine, will this also have to be given on a yearly basis, or will our immune system remain vigilant and prime based on what appears to be a two-dose regimen? In other words, you going to have to get the vaccinated once and then come back a few weeks later and get the second dose. This by the way a common way of giving child with vaccines, often have to be given in two or three separate doses. But the question is whether will our immune system remain prime against the coronavirus or whether you will have to get this on a yearly or every five or ten years like for instance, the Tetanus vaccine, which you need every ten years or so. That's one of the questions that we have and of course the other question is different strains of coronavirus. Does this messenger RNA technology that Pfizer is using, does this make it a vaccine that will be active against different coronavirus strains as they mutate? Or will you have to sort of develop a new one for each strain in the way that we do for influenza? I think as somewhat of an open question as well, and we will just have to wait and see what the signs tells us.