Should We Be Concerned About Coronavirus Variants?

Dr. Paul Offit discusses SARS-CoV-2 variants and the role of COVID-19 vaccines.


Should we be concerned about coronavirus variants?

Paul Offit, MD: Hi, my name is Paul Offit. I'm talking to you today from the Vaccine Education Center at the Children's Hospital of Philadelphia. It’s Tuesday, May 4th, 2021. I think what has happened with this pandemic as it swept across the world and has overwhelmed us is that we do have a way out of this, and the way out of this is vaccination.

There are two things that stand in the way of getting enough people vaccinated so that we can be protected. One is the anti-vaccine movement, which I think has created a lot of misinformation about vaccines that have caused some people to choose not to get them. The other thing that stands in the way of a successful vaccination program is that the coronaviruses mutate and start to create these so-called variants.

Now, to put this in perspective, the virus that originally swept through Wuhan and caused thousands of people to be hospitalized and die was not the virus that left China. The virus that left China was the first variant; it was called the D614G variant. That's the variant that swept across Europe. That's the variant that swept across the United States. That's the variance that's killed more than 500,000 people in this country. And the vaccines that were made, whether that's the mRNA vaccines of Pfizer or Moderna, or the vector virus vaccines of Johnson & Johnson and AstraZeneca, were made largely to protect against that first virus that left China. And those vaccines will also protect against other variants. So, for example, the so-called B.1.1.7 variant, or the UK variant, is very similar to that original virus that left China, so that immunization or natural infection with that variant — immunization with the current vaccines that we have or natural infection with that variant — will protect against disease caused by that variant.

But there are other variants which are of greater concern that have names like the South African variant or the Brazilian variant or the California variant or the New York variant and now the Texas variant that may have drifted somewhat farther away from the immunity that's been induced by natural infection or immunization. Now, the good news is those variants have not drifted so far away from the immunity induced by natural infection or immunization such that you would not be protected against severe/critical disease. You still are going to be protected if you've been naturally infected or vaccinated against those variants in terms of protection against severe/critical disease, the kind of disease that causes you to be hospitalized or go to the intensive care unit or die. But you are less likely to be protected against mild or moderate disease with those variants.

I think we will know that a critical line has been crossed when a variant is created that is resistant to all immunity induced by natural infection or immunization, so that even if you're vaccinated or even if you're naturally infected that you're in no way protected against disease caused by that novel variant. Now, that hasn't happened yet. If it does happen, I think we'll be well-prepared to make essentially a second-generation vaccine, which wouldn't be a booster dose; it would be essentially another vaccine because it wouldn't be boosting. It would just be a new vaccine to protect against this dramatically different variant. But that hasn't happened yet.

For now, the vaccinations that you're getting, or if you've been naturally infected, you are protected against severe and critical disease caused by any of the variants that are out there.

Thank you.

Related Centers and Programs: Vaccine Education Center

Last Reviewed on Jun 01, 2021