Dr. Anthony Fauci warned Americans on Sunday to fight back a sense of Covid-19 complacency even as coronavirus infections decline and some scientists predict that herd immunity is just around the corner.
"The slope that comes down is really great – it's very steep and it goes down very, very quickly. But we're still at a very high level," Fauci, a top pandemic adviser to President Joe Biden, told NBC . Meet the press. "
Fauci said he didn't want people to think "we're out of the woods now" just because the surge in infections dropped sharply.
"We're not. Because the baseline of daily infections is still very, very high," said Fauci. "It's not the 300,000 to 400,000 we had a while ago, but we really, really, really want to keep that baseline low before we start thinking we're not in the woods."
The pandemic, which first struck the nation early last year, has entered a new phase as the pace of vaccinations increases and the number of new infections decreases, even as the US is close to hitting the grim milestone of 500,000 Covid- 19- stand. related deaths.
The 7-day moving average of new infections was 71,717 on Saturday. As a CNBC analysis of Johns Hopkins University data, less than half of the 146,034 new daily infections reported earlier in the month, also a 7-day average.
More than 497,000 people have died of the disease in the United States since Sunday.
Fauci's comments to host Chuck Todd came in response to an opinion piece published Thursday in the Wall Street Journal by Dr. Martin Makary, a surgeon at Johns Hopkins University, who predicted the country will reach herd immunity in April.
Makary wrote that his prediction was based on data and science, as well as anecdotal evidence. He said that some medical experts privately agreed with his out-of-consensus view but warned him not to discuss it lest he inadvertently encourage the public to become complacent, fail to take precautions, or not receive the vaccine.
"On the current path, I expect Covid will be largely gone by April, which will allow Americans to resume normal lives," wrote Makary, saying that current estimates of natural immunity have likely been low.
Fauci said he was "not so sure" that the recent decline in infections was due to herd immunity or the phenomenon in which a critical number of people become resistant to the virus as a result of previous exposure or vaccination.
"Certainly the number of infected people contributes to this. Also a certain contribution with vaccines, not much," said Fauci. "I don't think we have vaccinated enough people yet to achieve herd immunity. I think you see nature peak and sink."
Dr. Scott Gottlieb, the former head of the Food and Drug Administration, also spoke on Sunday, saying in an interview on CBS News' Face the Nation that he expected the current decline in cases to continue.
Gottlieb said that if only 40% of the population have some form of immunity, the rate of infection can be slowed down significantly, a number lower than the 75% Fauci estimated to be the level for herd immunity.
In some parts of the country, Gottlieb added: "We just got that."
"I think we should be optimistic. I think we will continue to see a fall in infection rates in the spring and summer," he said.
The debate on the state and dynamics of the virus comes a year after the extended lockdowns and other preventive measures that stalled much of the economy, inflicted mental health trauma on a previously unknown number, and forced families apart.
Biden said achieving herd immunity could be a difficult task by the end of next summer that would force parents to grapple with the idea of starting another school year in pandemic conditions.
Even if the country contains the virus significantly, it is possible that some measures to protect against its spread may continue. Fauci said on CNN Sunday that even if the country gets a certain level of normalcy, Americans may wear masks to prevent the spread of Covid-19 over the next year.
"It is possible that it will," Fauci said of wearing masks in 2022. "It depends on the dynamics of the virus in the community. When you see the level is really, really, really low, I want it to be preserved. " It comes to a baseline so low that … there is a minimal, minimal threat to someone who is infected. "
Biden's cautious approach is a reverse of the abundant and sometimes ruthless optimism of his predecessor, former President Donald Trump. The measured remarks by the Biden government have sparked criticism from the opposite direction. Some say the government is setting targets that are too low given encouraging data.
The increase in the number of people receiving vaccinations has generated limited optimism. About 1.7 million vaccines are administered daily, up from the White House target of 1.5 million per day. Public health experts have said the rate could double by the end of the month if supply continues.
Despite these optimistic projections, major concerns remain about a number of new coronavirus mutations, some of which have been shown to be more transmissible than the dominant strain in the U.S. It is possible that mutant strains could prove resistant to the approved vaccines by experts, although experts have largely said they expect the current vaccines to work.
A strain of particular concern, first identified in the UK, doubles its presence in the US every 10 days, according to a study published earlier this month.
While the study found the strain was circulating at low absolute levels, it helped model the Centers for Disease Control and Prevention, which predicted the strain known as B.1.1.7., The dominant strain in the U.S. for the next month could be .
Dr. Michael Osterholm, former advisor to the Biden transition team, said Jan. 31 that B.1.1.7 is likely to see an increase in "the next six to 14 weeks".
"And when we see what my 45 years in the trenches tell me, we will see something we have never seen in this country," warned Osterholm.
The CDC has identified three mutant strains in the United States that "have particularly affected the world's leading public health and health care companies to date," including B.1.1.7 and variations identified for the first time in South Africa and Japan. The variant identified in Japan was found on travelers from Brazil.
Gottlieb said the variants represented "some risk", but that there was already "enough protective immunity that we can probably continue these [positive] trends".
The variations, he said, "will not be enough to reverse these trends at this point."
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