Speaking at an event hosted by the National Press Club on Friday, Dr. Anthony Fauci explained why he believes “we’re not going to get classical herd immunity” with the pandemic.
JEN JUDSON: Does the study published by the CDC on morbidity and mortality indicate the US has reached the herd immunity threshold? If not, when will we get there? Is that sooner or later than you expect?
ANTHONY FAUCI: Well, I recently wrote a paper a few weeks ago how the concept of how we classically think of herd immunity is likely unattainable in COVID-19. So I think we have to realize that, because herd immunity was the examples that I gave on the slides a few minutes ago when I showed what happens, what we did with measles, what we did with polio. Namely, you had enough immunity in the population with a stable virus that doesn't change. That's classical herd immunity.
It makes it very problematic to get herd immunity, which means there's enough protection in the community and enough stability of the virus that it doesn't change and enough durability of protection that you essentially don't have any infection in the community, similar to what we see now with measles and polio. Measles and polio is all over the world. In some countries, polio less so, but measles is widespread in many other countries. Yet we don't see measles in the United States because, A, people are immune to it, and B, the virus doesn't change.
We're not seeing that with SARS-CoV-2. We're seeing variants that emerge every few months. We've had alpha, beta, delta, omicron, BA.2, BA.4, BA.5. So it's very difficult to really get a strong classical herd immunity when you have immunity that wanes and a virus that, in fact, does not stay stable. And you have an anti-vax movement which prevents many of the people from getting vaccinated. So that's what I mean when I described recently we're not going to get classical herd immunity with SARS-CoV-2.