As New York officials on Thursday hurriedly launched a targeted lockdown to stamp out rising rates of positive coronavirus test results, chaos, confusion and tension erupted over restrictions that are closing schools and businesses and greatly limiting attendance at places of worship.
There were competing hot-spot maps, issued by Mayor Bill de Blasio of New York City and then by Gov. Andrew M. Cuomo, which overlapped and contradicted each other. Schools and businesses that were to be shut down on one map were not on the other. The city, where the rules took effect on Thursday in parts of Brooklyn and Queens, made a searchable online database of addresses available so New Yorkers could determine which zone they were in.
Two lawsuits were also filed on Thursday, one by an Orthodox Jewish group and the other by the Roman Catholic Diocese of Brooklyn, to stop the state from enforcing the governor’s restrictions on houses of worship.
The legal actions came after ultra-Orthodox Jews in the Borough Park neighborhood of Brooklyn this week lit masks on fire and attacked an Orthodox reporter who has documented local resistance to social distancing.
And in other Brooklyn neighborhoods like Bensonhurst and Windsor Terrace, parents rallied against the sudden closure of schools.
The targeted lockdown, in place for two weeks, divides virus hot spots into three color-coded zones of red, orange or yellow, with nonessential businesses in the hardest-hit areas required to shut down. Restaurants and bars in a red zone, which has the most severe rules, can only offer takeout and delivery, just like in the spring. Houses of worship are limited to just 10 individuals, a number that coincides with the minimum requirements of a Jewish prayer service.
After two weeks, Mr. de Blasio said Thursday that the city would work with the state to reassess whether a longer timetable were needed.
“This is a turnaround that, if we do it right, could only take a few weeks,” Mr. de Blasio said Thursday. “If we don’t do it right, it could go a lot longer.”
Today we establish clear limits for areas where we see high positivity: The Cluster Action Initiative.
Locations will be categorized either Red, Orange, or Yellow, based on proximity to the cluster.
The severity of the problem will determine the response. pic.twitter.com/707FYGHB0g
— Andrew Cuomo (@NYGovCuomo) October 6, 2020
The city shut down 61 public school sites on Thursday, he said; in total, 153 locations had been closed in the red and orange zones.
Earlier in the week, Gov. Andrew M. Cuomo announced that schools in nine ZIP codes in Brooklyn and Queens had to be closed for in-person instruction on Tuesday. But when the state released updated guidance, some of those schools fell into yellow zones, in which schools can remain open. Mr. de Blasio said on Thursday that 16 schools in those areas will remain closed for now.
“We’re going to keep those schools closed too because the city believes fundamentally those schools have to be closed as part of the overall strategy,” the mayor said.
City Hall officials were perplexed by the governor’s new maps, and frustrated by their lack of clarity, but thankful that he had agreed to do something, a de Blasio administration official said. But the map files the state had given the city were flawed, two city officials said, with some geographic borders not corresponding to streets, leaving people to guess whether their schools or stores were required to close.
Restrictions: Major Minor
Restrictions: Major Minor
Restrictions: Major Minor
Robert Mujica, the governor’s budget director and a member of his coronavirus task force, said city officials are merely upset that the governor’s office second-guessed them, and that they should have worked with the state earlier in the process.
“Their plan was to put this in place on Wednesday,” Mr. Mujica said. “We, having no info on this until Sunday afternoon, worked around the clock to deal with their timeline and get the maps drawn in a way that actually made sense.”
On Thursday, the rules also became the subject of litigation, as an Orthodox Jewish group and the Roman Catholic Diocese of Brooklyn sought to block the enforcement of capacity restrictions at houses of worship.
“The executive orders this week have left us with no other option than to go to court,” Nicholas DiMarzio, Bishop of Brooklyn, said in a statement, adding that it was “an insult to once again penalize all those who have made the safe return to church work.”
Mr. de Blasio also said that the seven-day average rate of positive virus test results was 1.56 percent, slightly lower than the rate reported on Wednesday.
Statewide, the daily positivity rate was 1.26 percent, Mr. Cuomo said, adding that hospitalizations were up from the previous day, to 754.
President Trump’s doctor said on Thursday that he’s completed his treatments to alleviate the symptoms of the coronavirus and that he anticipates that the president will be able to resume “public engagements” on Saturday.
The forecast about Mr. Trump’s condition came from the White House physician, Dr. Sean Conley, in a note updating people on his health. Mr. Trump announced shortly before 1 a.m. on Friday, Oct. 2, that he and the first lady, Melania Trump, had tested positive for the virus; White House officials have declined to say when he last tested negative.
He was taken to Walter Reed National Military Medical Center Friday afternoon. Officials initially described the president’s symptoms as mild, but The Times and other news organizations reported Saturday that Mr. Trump had been administered supplemental oxygen because his blood oxygen dropped to a level that was concerning. His lung scans had “expected findings,” Dr. Conley said on Sunday, although he declined to say what that meant.
In the note on Thursday, which was first reported by N.P.R., Dr. Conley said that Mr. Trump has remained “stable” and “devoid” of symptoms that would suggest the illness was progressing.
“Saturday will be day 10 since Thursday’s diagnosis, and based on the trajectory of advanced diagnostics the team has been conducting, I fully anticipate the president’s safe return to public engagements at that time,” Dr. Conley said.
The Centers for Disease Control and Prevention says those who test positive for the coronavirus should isolate themselves from others for a minimum of 10 days after testing positive, or for at least 10 days after symptoms first appear. Some people with a moderate or severe case of the virus can stay infectious for 20 days or perhaps even longer, according to the C.D.C.
A person close to the White House said that Mr. Trump is discussing holding a public event with people on the White House grounds on Saturday.
Shortly after Dr. Conley’s memo, Mr. Trump’s re-election campaign released a statement calling for the second presidential debate to take place as originally scheduled. “There is therefore no medical reason why the Commission on Presidential Debates should shift the debate to a virtual setting, postpone it, or otherwise alter it in any way,” the statement said.
The Senate majority leader, Mitch McConnell, said Thursday that he had been avoiding the White House since midsummer because of concerns that officials there were not taking proper precautions to guard against the spread of coronavirus.
“My impression was that their approach to how to handle this was different from mine and what I insisted that we do in the Senate, which is to wear a mask and practice social distancing,” Mr. McConnell told reporters.
The Kentucky Republican said he had not visited the White House since Aug. 6, when he met with President Trump to discuss the status of negotiations over additional stimulus legislation.
The decision appears to have been a prudent one now that the White House has become a virus hot spot, with Mr. Trump the most prominent to test positive for the virus and contract Covid-19, the disease.
More than a dozen White House guests and employees, including two of Mr. McConnell’s fellow Senate Republicans, were infected after attending an event Mr. Trump held last month to announce his Supreme Court nominee, Judge Amy Coney Barrett. Mr. McConnell, who is leading the drive to confirm Judge Barrett, was noticeably absent from the largely maskless group gathering.
The majority leader did not specifically comment on Judge Barrett’s nomination ceremony.
Though he has closely aligned himself with Mr. Trump politically, Mr. McConnell has consistently struck a different, more sobering tone when discussing the virus. He has publicly urged Americans to wear masks, repeatedly warned that the pandemic’s grip will be long and said he believed a vaccine would not be widely available until next year.
“This is not over,” Mr. McConnell said again on Thursday. “We are going to have to work through it.”
The antibody cocktail for Covid-19 that President Trump touted on Wednesday afternoon was developed with cells originally derived from fetal tissue, a practice that his administration has moved to restrict.
In June 2019, the Trump administration suspended federal funding for most new scientific research involving fetal tissue derived from abortions.
“Promoting the dignity of human life from conception to natural death is one of the very top priorities of President Trump’s administration,” the Department of Health and Human Services said in a statement in 2019, around the time of the ban.
“Intramural research that requires new acquisition of fetal tissue from elective abortions will not be conducted,” the statement added.
Mr. Trump last week received Regeneron’s cocktail of monoclonal antibodies — essentially, antibodies synthesized in living cells and administered to help the body fight off the infection.
To develop the antibodies, Regeneron relied on 293T, a cell line derived from the kidney tissue of an aborted fetus in the 1970s. At least two companies racing to produce vaccines against the coronavirus, Moderna and AstraZeneca, also are using the cell line.
Remdesivir, an antiviral drug Mr. Trump received, also was tested using these cells.
“293Ts were used in testing the antibodies’ ability to neutralize the virus,” said Alexandra Bowie, a spokeswoman for Regeneron. “They weren’t used in any other way, and fetal tissue was not used in the research.”
In a video released Wednesday, Mr. Trump praised Regeneron’s treatment, calling it a “cure” for Covid-19 and promising to provide it free to any patient who needed it. The company said on Wednesday that it had applied to the Food and Drug Administration for emergency use authorization.
Scientists noted that the trials of the antibody cocktail are far from complete, and that Mr. Trump is taking a variety of drugs that may have explained why he said he felt better.
Dr. Anthony S. Fauci, the nation’s leading expert on infectious diseases, said that Mr. Trump might be right that the treatment he received has helped him in his fight with Covid-19 — but that his case alone doesn’t prove it.
“I think it’s a reasonably good chance that the antibody that he received, the Regeneron antibody, made a significant difference in a positive way in his course,” Dr. Fauci, who is not involved in the president’s care, said on Thursday during an interview on MSNBC.
But he pushed back against Mr. Trump’s claim that the treatment has now been shown to be a “cure” for the disease, which has killed more than 210,000 Americans so far.
The White House did not immediately respond to a request for comment.
In July, the International Society for Stem Cell Research sent a letter to the Human Fetal Tissue Research Ethics Advisory Board at the National Institutes of Health, urging the board to allow fetal tissue to be used to develop treatments for Covid-19 and for other diseases.
“Fetal tissue has unique and valuable properties that often cannot be replaced by other cell types,” the letter said.
In August, the board rejected 13 of the 14 proposals involving fetal tissue. The approved proposal relied on tissue that had already been acquired.
William Foege, a famed epidemiologist and the former director of the Centers for Disease Control and Prevention, said Thursday that President Trump and Vice President Mike Pence had “their knees on the neck of the public health community,” and called on the current C.D.C. director to stand up to them — even at the risk of getting fired.
“Silence becomes complicity, and I think the one person that might have turned this around would be the director of the C.D.C.,” Dr. Foege, who served Republican and Democratic presidents, said in an interview.
Dr. Foege, 84, helped lead the successful effort to eradicate smallpox in the 1970s and ran the C.D.C. under Presidents Jimmy Carter and Ronald Reagan. He is considered a giant in the world of public health. Earlier this week, U.S.A. Today published a private letter that he wrote to the current C.D.C. director, Dr. Robert R. Redfield, advising him to speak out about the administration’s failures.
In his first extensive comments since then, Dr. Foege reiterated that sentiment, saying that beyond coming clean with the public, Dr. Redfield must work to shore up his beleaguered staff and restore the institution’s battered reputation.
“I think he would level with C.D.C. employees and let them know what the White House has actually done — some of it is public — the fact that they were willing to put things on the C.D.C. website, that they would overrule the recommendation of C.D.C.,” Dr. Foege said, adding, “If he said, ‘I will stand behind you for as long as I’m here,’ and then if he gets fired he gets fired with his head held high.”
The White House rejected the agency’s initial plan for reopening the country and pressured the C.D.C. to play down the risk of sending children back to school. More recently, a disputed guidance pulling back on coronavirus testing was posted on the C.D.C.’s website over the objections of career scientists.
And on Wednesday, the White House released an unusual letter written by Dr. Redfield that vouched for Mr. Pence’s health in advance of the vice-presidential debate. Dr. Foege said he was unaware of it, “but it sounds very manipulative.”
Dr. Foege suggested that Dr. Redfield was in a nearly impossible situation, working for a president who has declared all-out war on his agency and accused its scientists of being part of a “deep state” conspiracy against him.
“I like the man, and I am impressed that he wants to do the right thing — that this is not someone who is deliberately trying to do the wrong thing,” Dr. Foege said, adding “but he’s with this great contingent of people who can’t stand up to a bully, and that’s something I don’t understand.”
Dr. Foege’s letter, dated Sept. 23, opened by saying he woke up every day thinking of the “terrible burden” on Dr. Redfield. He said Thursday that he had written it out of “frustration” that had been “building up” and that he never intended for it to become public. In the interview, Dr. Foege said that he and Dr. Redfield have had an exchange about the letter, though he declined to provide specifics about their conversations.
Dr. Redfield has had no comment.
On Thursday, seven states reported single-day records. Montana, North Dakota, Utah, Wisconsin and Wyoming set records for new cases, according to a New York Times database, and South Dakota and Tennessee set records for deaths.
President Trump released another video message on Thursday, promising to make the experimental treatment that he received for Covid-19 “available immediately” and “all free.”
Mr. Trump addressed the video, which was taped outside the White House and posted on Twitter, to older Americans, whom he called “my favorite people in the world.” Repeating a claim he made yesterday, the president referred to a treatment, which he did not name, as a “cure.”
There is no known cure yet for the coronavirus.
Mr. Trump appeared to be referring to an antibody treatment being developed by the drug company Regeneron, which he was given on an emergency basis when he was in the hospital. That treatment is still in late-stage clinical trials. Although early data has been promising, experts have said there is no way to know whether it helped Mr. Trump.
Mr. Trump also repeated a suggestion that treatments could soon be authorized by the Food and Drug Administration for emergency use. He did not offer an explanation for how he would make the medication free or how he intended to “get it to you soon.” However, Regeneron has received over $500 million from the federal government to develop and manufacture its antibody therapy, and as part of that deal, has said it would be made available at no cost to Americans.
On Wednesday, Regeneron said that it had applied for emergency authorization of its treatments, and said it had enough doses for 50,000 patients, and would have enough for up to 300,000 people by the end of the year.
“We’re taking care of our seniors,” the president said. “You’re not vulnerable, but they like to say ‘the vulnerable,’ but you’re the least vulnerable. But for this one thing you are vulnerable, and so am I.”
Polling suggests that Mr. Trump is struggling to win over older Americans, a crucial voting bloc for Republicans. Although he led Hillary Clinton by five points among the cohort in 2016, several polls this week show the president trailing Joe Biden among these voters by at least 20 points.
Also on Thursday, Mr. Trump said he would not participate in a virtual debate, speaking on Fox Business Network minutes after the Commission on Presidential Debates announced that the next debate would be virtual because of virus concerns. Bill Stepien, Mr. Trump’s campaign manager, said in a statement that the commission’s decision was “pathetic” and that “President Trump will have posted multiple negative tests prior to the debate, so there is no need for this unilateral declaration.”
Mr. Stepien’s claim about Mr. Trump testing positive over the next week is unsubstantiated, because the virus is notoriously unpredictable.
The president also repeated calls to hold China responsible for the pandemic. “We are making tremendous progress with this horrible disease that was sent over by China,” he said. “China will pay a big price for what they did to the world and us.”
Defiance of coronavirus rules in rural India is propelling the nation’s virus caseload toward the No. 1 spot globally. Infections are rippling into every corner of this country of 1.3 billion people. The Indian news media is calling it “The Rural Surge.”
In the Indian megacities where the pandemic first hit, vigorous public awareness campaigns have left the populace mostly on guard. But when it comes to government efforts to contain the virus, rural India is resisting.
In many villages, no one is wearing masks. There is no social distancing. People are refusing to get tested and they are hiding their sick. Many believe the government is overstating the severity of the pandemic and showing no sensitivity to the economic hardship that they are suffering.
That dynamic has helped India catch up with the United States in terms of total infections. U.S. cases are near 7.6 million, compared with India’s 6.8 million, according to a New York Times database. But India outpaces new American cases by 30,000 or so each day, putting it on a path to potentially surpass the United States in the coming weeks.
Officials say India’s caseload is rising because nearly one million tests are being performed each day, five times the number a few months ago. They also point to India’s relatively low death rate, about an eighth or ninth of those of the United States, Spain, Brazil and Britain.
Scientists say this is mainly because India’s population is younger and leaner, though they caution that most deaths in India, from any cause, are not investigated. And India’s deaths are steadily ticking up, by about 1,000 a day, now totaling about 105,000.
In other developments around the world:
On Wednesday, Brazil passed the five million case mark. The milestone came as the spread of the virus has been slowing down for over a month — an achievement many public health experts believe has little to do with the government’s handling of the crisis, but rather how thoroughly the virus has ravaged the country. In the city of Manaus, in the state of Amazonas, one of the most severely hit by the virus, the number of cases began to increase, especially among young people, in recent weeks.
The United Nations official overseeing the organization’s refugee relief operations is self-isolating after having tested positive for the coronavirus. Filippo Grandi, the high commissioner for refugees, disclosed his diagnosis in a Twitter post on Wednesday, saying he had mild symptoms and hoped to recover soon. Mr. Grandi, 63, had in recent weeks traveled to Brussels, Jordan, Syria and Lebanon. Stéphane Dujarric, the U.N. spokesman, told reporters on Thursday that “all close contacts were informed about the High Commissioner’s situation” and that seven of them are also self-isolating.
The British government is considering a tiered system that would tighten restrictions on pubs and restaurants in the areas of England with the highest rates of infection, according to the BBC and other media outlets. A ban on overnight stays away from home could also be introduced for the worst-affected areas, but schools would remain open. Despite local lockdowns in several cities in the north of England, the country’s coronavirus caseload has continued to increase, with Britain reporting an average of 13,000 new cases a day over the past week.
The European Union signed a deal with Gilead, the California-based pharmaceutical company, to ensure uninterrupted access to an antiviral drug being used to treat Covid-19. Veklury, also known as remdesivir, has been authorized by more than 50 countries, including the United States and in Europe, for the treatment of Covid-19 patients needing supplemental oxygen. The deal signed between Gilead and the European Commission, the executive arm of the European Union, would allow all members of the European Union, as well as the United Kingdom, Iceland, Liechtenstein, Norway and several Balkan countries to buy up to 500,000 treatment courses in the next six months.
In Germany, the head of the federal institute responsible for tracking the coronavirus warned on Thursday that the country could soon see an “uncontrolled” spread of the virus. “It is possible that we see more than 10,000 new cases per day,” the official, Lothar Wieler, who leads the Robert Koch Institute, said at a news conference. Germany recorded at least 4,000 new daily cases on Wednesday and has a daily average of at least 2,600 new cases over the past week, according to a New York Times database.
Hong Kong’s health secretary, Sophia Chan, said Thursday that the city was considering legal options for mandatory testing as it prepared for a new wave of coronavirus infections. She noted that research by the University of Hong Kong showed the rate of the spread was increasing once again. On Thursday, Hong Kong reported 18 new coronavirus cases, 14 of which were locally transmitted.
Madrid’s highest regional court on Thursday annulled a lockdown imposed by Spain’s central government on the capital region. The court said that the central government did not have jurisdiction to institute restrictions that affected fundamental rights and the freedom of movement. The ruling is a major setback for the central government, and underlines both the political tensions and legal uncertainty in Spain over how to respond to the latest wave of virus cases.
Swedes pay some of the highest taxes on earth in exchange for extensive government services, including state-furnished health care. Yet among the nearly 6,000 people whose deaths have been linked to the coronavirus in Sweden, 2,694, or more than 45 percent, were among the country’s most vulnerable citizens — those living in nursing homes. It is in part the story of how Sweden’s famously generous social safety net has been eroding.
The El Paso Health Department reported 523 new cases of Covid-19 on Thursday, a record for the West Texas city. The city also reported four deaths.
There are 4,929 active cases of the coronavirus in El Paso, the sixth-largest city in Texas. After declining in early August, cases began spiking dramatically in mid-September.
“We are deeply concerned with the current rising trends we are experiencing on number of positive cases, hospitalizations and deaths due to COVID-19,” Dr. Hector Ocaranza of the El Paso Health Authority said in a news release on Thursday.
A New York Times analysis in July of mask-wearing patterns across the United States found that mask-wearing rates were high in El Paso at the time. The city’s mayor, Dee Margo, a Republican, has made a point of wearing a mask in public, and the city enacted a mask mandate in June.
But the news release on Thursday cited “virus fatigue” as a probable cause for the spike, and urged residents to remain vigilant in taking precautions, and isolating after a diagnosis.
“Without a vaccine or medication to cure the disease,” Dr. Ocaranza said, “it’s up to each and every one of us to stop the spread of disease.”
A day earlier, Bishop Mark Seitz of the Catholic Diocese of El Paso announced that he had tested positive for the virus. The bishop said that he had no symptoms, and that he would self-isolate for the 10 days.
American Legion posts across the country provide veterans in need with financial and emotional support. The post in Wilmette, Ill., was like a community center, with Bingo and spaghetti nights.
After operating for more than a century, the Huerter-Wilmette Post 46 is now closing. The post was named after Peter Huerter, a local soldier who died during World War I of the Spanish flu while he was on his way to serve in France.
“Covid complicated everything,” said Michael Jonscher, 58, a Navy veteran and the current adjutant of Wilmette’s Post 46.
With dwindling numbers, members of the post had been planning to merge with another nearby, but the pandemic has made the goodbye more painful. “We are afraid to even get together,” said Mr. Jonscher. “That’s where the gut punch is.”
In the 1970s, the post had more than 400 members; today there are fewer than 50, said Andrew Haszlakiewicz, 74, a Vietnam veteran and the post’s commander.
But Mr. Haszlakiewicz said he is hopeful that through the merger with Morton Grove Post 134, which has 1,000 members, the Wilmette group will be able to hold some of their cherished traditions, such as the Nov. 11 Veterans Day ceremony — in a socially distant manner, of course.
The French authorities are tightening virus restrictions in a growing number of big cities as cases rise and hospitals come under increasing strain.
The Paris and Marseille regions have already been placed on the country’s highest alert level, which requires the closure of all bars, gyms and clubs for at least two weeks. Classrooms and universities are limited to half capacity and restaurants can only remain open if they follow a strict health protocol.
“Unfortunately, the health situation continues to deteriorate in France,” Olivier Véran, France’s health minister, said on Thursday as he announced that four cities — Lille, Grenoble, Lyon and Saint-Etienne — also would be placed on maximum alert as of Saturday.
France is bracing itself for a return to restrictions that were put into place when the virus first hit the country, although there have been protests against the idea in the south of the country. According to a survey published on Sept. 26 by IFOP, one of France’s leading polling firms, 72 percent of French citizens would be in favor of a new, nationwide lockdown.
France reported a record daily count of more than 18,700 new cases on Wednesday, according to a Times database, and Covid-19 patients now occupy a quarter of intensive care unit beds nationwide, said Aurélien Rousseau, the head of the health authority for the Paris region.
In total, there have been nearly 654,00 coronavirus cases in France, and almost 32,500 people have died, the Times database shows.
On Thursday, hospitals in the Paris region activated emergency measures that were used previously in March and April to cope with an influx of patients. The efforts involved postponing non-urgent surgeries and calling staff members back from leave.
Rousseau said that enacting such measures was “an important decision” that “means that we are going to face a very strong wave, and that we have to put all forces into the battle.”
Across the country, millions of first-year students are arriving on college campuses during a pandemic. That means classes conducted mostly online, dinners in dorm rooms and difficulty getting to know professors and peers. Some look forward to fleeting moments to be with others, like elevator rides. Others force themselves to take walks to be sure they see sunlight.
Among them is Elle Fleenor, who hunkered down for two weeks of quarantine when she arrived on the campus of Butler University in Indianapolis. She attended orientation and lectures on Zoom, picked up food from the dining hall to eat in her room and barely interacted with anyone beyond her dorm building’s walls.
Ms. Fleenor, a first-year student from Scottsburg, Ind., knew she wouldn’t have the college experience she had imagined. But she wasn’t prepared for how the precautions her school was taking to slow the spread of the coronavirus would complicate her efforts to make friends, and how isolated that would make her feel.
“It’s been very hard, very lonesome,” Ms. Fleenor said. “As a freshman, being hit with all this is extremely difficult.”
The first semester of college is challenging even in normal times, as students get used to being away from home, their families and lifelong friends. This year, psychologists and other experts fear that the necessary precautions taken by colleges and universities, many of them coronavirus hot spots, will increase the loneliness and isolation.
“We’re receiving recommendations and restrictions aimed at limiting the spread of the virus that also limit our ability to connect with others,” said Julianne Holt-Lunstad, a professor of psychology and neuroscience at Brigham Young University.
Dr. Anthony S. Fauci, the nation’s leading expert on infectious diseases, said that President Trump might be right that the experimental treatment he received and promoted has helped him in his fight with Covid-19 — but that his case alone doesn’t prove it.
“I think it’s a reasonably good chance that the antibody that he received, the Regeneron antibody, made a significant difference in a positive way in his course,” Dr. Fauci, who is not involved in the president’s care, said on Thursday during an interview on MSNBC.
He pushed back against Mr. Trump’s claim that the treatment has now been shown to be a “cure” for the disease, which has killed more than 210,000 Americans so far.
“When you have only one, you can’t make the determination that that’s a cure,” he said. “You have to do a clinical trial involving a large number of individuals, compared either to a placebo or another intervention.”
The manufacturer, Regeneron, has applied to the Food and Drug Administration for emergency approval of the experimental treatment, a cocktail of monoclonal antibodies.
Mr. Trumped received the Regeneron cocktail on Friday after he announced that he had tested positive for coronavirus. He has also received other treatments that are used for patients with severe cases of Covid-19, including remdesivir and dexamethasone.
In a five-minute video on Wednesday, Mr. Trump said that it was a “blessing from God” that he had been infected with the coronavirus and that the Regeneron cocktail had suddenly made him feel better. “I felt unbelievable,” he said. “I felt good immediately.”
The president said he would make sure that hundreds of thousands of doses would be available to Americans soon, free of charge, and he gave the impression that he would push the F.D.A. to approve the treatment. The company, however, has said that access to the treatment would be extremely limited at first, with only enough doses for 50,000 patients.
The president’s true condition is unclear. The White House doctor overseeing his care, Dr. Sean P. Conley, has admitted that he misled the public when Mr. Trump was hospitalized at Walter Reed National Military Medical Center.
In the televised interview, Dr. Fauci said it was known that a Covid-19 patient can feel good one day and go downhill quickly the next.
“The chances of that happening? I don’t know,” Dr. Fauci said of Mr. Trump’s case. “As good as he looks, I don’t think that’s going to happen, but I don’t know.”
Earlier in the week, in a virtual event for Cornell University, his alma mater, Dr. Fauci spoke about the dangers of sending the public conflicting signals on important health issues like new treatments for Covid-19.
“I try to, the best of my ability, in being very consistent in my messaging based on facts and scientific data,” Dr. Fauci said, according to The Cornell Daily Sun. “But when there are mixed messages coming out of any institution, including the federal government, there is confusion as to what people should do.”
He added, “Personally contradicting the president of the United States publicly is not a good thing if I want to get my job done.”