Herd Immunity Strategy to Fight Coronavirus Can Be Dangerous, Experts Warn

After months of effort to limit the spread of the coronavirus in the United States, herd immunity has emerged as a controversial topic.

White House Coronavirus Task Force member Dr. Scott Atlas responded to a report on Monday that claimed he is a proponent of a "herd immunity" strategy to combat COVID-19. "I've never advocated that strategy," Atlas said at a press conference in Florida, CNN reported.

Such an approach -- similar to what was pursued in Sweden -- would mean that many people nationwide would have to get sick with the coronavirus in order to build up a natural immunity across communities. As the virus spreads and sickens people, many could die in the process.

Atlas explicitly denied that he is pushing a herd immunity strategy, but an administration official told CNN all of the policies Atlas has pushed for are in the vein of a herd immunity strategy.

Atlas has rejected the need for widespread community testing, arguing that the administration should focus almost exclusively on protecting and testing elderly populations while pushing for the rest of the economy to return to normal, this official said.

"Everything he says and does points toward herd immunity," the senior administration official said.

About 2 million Americans could die in the effort to achieve herd immunity to the coronavirus, Dr. Leana Wen, emergency physician and CNN medical analyst, said on Monday.

Wen told CNN's Brianna Keilar that she has "huge concerns" about a herd immunity approach and much is still unknown about how long immunity to COVID-19 might last.

"If we're waiting until 60% to 80% of people have it, we're talking about 200 million-plus Americans getting this -- and at a fatality rate of 1%, let's say, that's 2 million Americans who will die in this effort to try to get herd immunity," Wen said. "Those are preventable deaths of our loved ones that we can just not let happen under our watch."

Maria Van Kerkhove, the World Health Organization's technical lead for coronavirus response, said during a media briefing in Geneva last week that "herd immunity" is typically discussed in the context of vaccinations -- not as a response to a pandemic.

"Normally when we talk about herd immunity, we talk about how much of the population needs to be vaccinated to have immunity to the virus, to the pathogen, so that transmission can no longer take place or it's very difficult for a virus or a pathogen to transmit between people," Van Kerkhove said.

"If we think about herd immunity in the natural sense of just letting a virus run, it's very dangerous," she said. "That means that many people are infected, many people will need hospitalizations and many people will die."

Herd immunity refers to a specific threshold of protection needed for a certain population or community to have against an infectious disease to keep it at bay -- and that protection can come from either prior infections or vaccination, Dr. Amesh Adalja, senior scholar at the Johns Hopkins University Center for Health Security, told CNN on Monday.