Sen. Rand Paul misleadingly suggested that much of the U.S. population has immunity to the coronavirus due to previous exposure to similar viruses

Dr. Anthony Fauci and CDC director Robert Redfield testified on the coronavirus response before the Senate on September 23. In questioning Dr. Fauci, Kentucky Senator Rand Paul misleadingly suggested that much of the U.S. population has immunity to the coronavirus due to previous exposure to similar viruses. But scientists say any possible protection is theoretical and can’t be relied upon to control the pandemic.

As reported by Factcheck.org

Coronavirus task force member Dr. Scott Atlas and Sen. Rand Paul have misleadingly suggested that much of the U.S. population has immunity to the coronavirus due to previous exposure to similar viruses. But scientists say any possible protection is theoretical — and can’t be relied upon to control the pandemic.

Paul, who is a Republican from Kentucky, broached the idea of preexisting immunity to the coronavirus during a Senate hearing on Sept. 23. 

In a heated exchange with Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, Paul argued that the reason why New York’s outbreak is now largely under control is because of community, or herd, immunity — and not because the population followed public health guidelines.

Fauci, Sept. 23: Right now, if you look at what’s going on right now, the things that are going on in New York to get their test positivity 1% or less is because they are looking at the guidelines that we have put together from the task force of the four or five things of masks, social distancing, outdoors more than indoors, avoiding crowds and washing hands.

Paul: Or they’ve developed enough community immunity that they’re no longer having the pandemic because they have enough immunity in New York City to actually stop it.

Fauci: I challenge that, senator. … You were not listening to what the director of the CDC said, that in New York, it’s about 22%. If you believe 22% is herd immunity, I believe you’re alone in that.

Paul: There’s also the preexisting immunity of those who have cross-reactivity, which is about a third of the public in many estimates … which would actually get you to about two-thirds.

Fauci: I’d like to talk to you about that also because there was a study that recently came out that preexisting immunity to coronaviruses that are common cold do not cross-react with the COVID-19.

It’s unclear which study Fauci was thinking of — NIAID’s press office did not respond to our inquiry — but Paul’s office told us he was referencing research on immune cells known as T cells from the La Jolla Institute for Immunology.

As we’ll explain, there are studies showing that some people have T cells that can recognize SARS-CoV-2, or the novel coronavirus. But there’s no reason to think those cells would contribute to herd immunity, which occurs when enough of the population is immune to prevent spread of the disease.

Scientists have generally found that people do not harbor cross-reactive antibodies that can actually prevent infection with the coronavirus and that would be meaningful for herd immunity.