Countries such as Israel, Germany and the U.K. have announced they will offer a third dose of the coronavirus vaccine to vulnerable populations. Will the U.S. follow suit? And why would it be needed? Dr. Gigi Gronvall and Dr. Chris Beyrer explain.
GIGI GRONVALL: So I think it helps to kind of remind people how the vaccines work. So they're an education program for your immune system. Your immune system has lots of components. And so when you get vaccinated, it's just basically like a training program so that when your body encounters the real virus, it's a much faster process to get things in gear, to pounce on it, and to keep the virus from making a gazillion copies of itself.
So after two doses, most people have all the parts in place to be able to do just that. And it all goes on in the background. You're not aware that your body is going to war against this virus. But for some people, it takes a little bit more time to get that process in gear. And so that's why you would consider an extra training session, an extra dose of the vaccine.
So that's why right now, some countries are recommending that people who have known immune immunological problems, people who, for example, have liver transplants or are on certain medications, that they might benefit from having that extra training so that if they encounter the SARS-CoV-2, that they're ready to go. And so I think that is likely to happen in the US. I think some people are already doing it even without the recommendations of the CDC.
CHRIS BEYRER: Now, all of this, of course, is complicated by the variants, because these vaccines-- for example, the Pfizer and Moderna were based on an isolate of the very earliest COVID cases in Washington state. So that is really as close to the Wuhan strain as you're going to get. That's the original strain. That strain is essentially extinct.
It's just been completely overgrown by these later variants. And so what probably is going to happen is not that you're going to give another dose of the original vaccine, but all the companies, and the NIH, and many others, many investigators are working on boosters against the new variants. And that would not be the same precise vaccine. The most important thing is to get fully immunized, either with two doses of the two-dose vaccines or one dose of the one-dose vaccines.
And that is for all of our individual benefit, but it's also really important to get control of this Delta variant. You know, we need to do much better at that. That is the fundamental. And you know, here we are in a situation where people who have already had two doses may be contemplating boosters when our biggest problem in the United States right now is the substantial proportion of Americans who are not immunized at all. And that's the focus.