Group items tagged

Are paper surgical single-use masks better or is a cloth mask OK? The evidence on any mask use, outside of surgical masks, is still emerging: there appears to be some benefit, but the exact parameters of which masks are the best and the extent to which they protect the wearer or those around them are still being figured out. A tighter fitting around the face is probably better, but the CDC suggests any covering, including a bandana, is better than none.

heavyweight “quilter’s cotton” or multiple layers of material. Scarves and bandana material were less effective, but still captured a fraction of particles.

Replace the mask when it is damp. To remove your mask, take it off using the elastic tags, without touching the front and discard immediately into a closed bin or, if the mask is reusable, directly into the washing machine.

How often do you need to wash masks? They should be washed after each use. The US Center for Disease Control suggests “routinely”.

if every person in the UK used one single-use mask each day for a year, an extra 66,000 tonnes of contaminated plastic waste would be created. The use of reusable masks by the general population would significantly reduce plastic waste and the climate change impact of any policy requirements for the wearing of face masks, according to the UCL team, led by Prof Mark Miodownik. They say that according to the best evidence, reusable masks perform most of the tasks of single-use masks without the associated waste stream.

The allowance for surgical masks made more sense when scientists initially thought the virus was spread by large droplets. But a growing body of research shows that it is spread by minuscule viral particles that can linger in the air as long as 16 hours.

A properly fitted N95 respirator will block 95% of tiny air particles – down to 0.3 micron in diameter, which are the hardest to catch – from reaching the wearer’s face. But surgical masks, designed to protect patients from a surgeon’s respiratory droplets, aren’t effective at blocking particles smaller than 100 microns, according to the mask maker 3M. A Covid-19 particle is smaller than 0.1 micron, according to South Korean researchers, and can pass through a surgical mask.

said Katie Scott, an RN at the hospital and vice-president of the Michigan Nurses Association. Employees who otherwise treat Covid-19 patients receive surgical masks.

A 2013 Chinese study found that twice as many health workers, 17%, contracted a respiratory illness if they wore only a surgical mask while treating sick patients, compared to 7% who continuously used an N95, per a study in the American Journal of Respiratory and Critical Care Medicine.

Earlier this month, the national Teamsters Union reported that 64% of its healthcare worker membership – which includes people working in nursing homes, hospitals and other medical facilities – could not get N95 masks.

The CDC’s recent advice on surgical masks contrasts with another CDC web page that says surgical masks do “NOT provide the wearer with a reliable level of protection from inhaling smaller airborne particles and is not considered respiratory protection”.

That matches CDC protocol, but leaves nurses like Scott – who has read the research on surgical masks versus N95s – feeling exposed.

At Michigan Medicine, employees are not allowed to bring in their own protective equipment, according to a complaint the nurses’ union filed with the Michigan Occupational Safety and Hazard Administration. Scott said friends and family have mailed her personal protective equipment (PPE), including N95 masks. It sits at home while she cares for patients.

“To think I’m going to work and am leaving this mask at home on my kitchen table, because the employer won’t let me wear it,”

News reports from Kentucky to Florida to California have documented nurses facing retaliation or pressure to step down when they’ve brought their own N95 respirators.

In New York, the center of the US’s outbreak, nurses across the state report receiving surgical masks, not N95s, to wear when treating Covid-19 patients, according to a court affidavit submitted by Lisa Baum, the lead occupational health and safety representative for the New York State Nurses Association (NYSNA).

White House to invoke the Defense Production Act, a Korean war-era law that allows the federal government, in an emergency, to direct private business in the production and distribution of goods.

provide health care workers with protective equipment, including N95s masks, when they interact with patients suspected to have Covid-19.

“Nurses are not afraid to care for our patients if we have the right protections,” said Bonnie Castillo, the executive director of National Nurses United, “but we’re not martyrs sacrificing our lives because our government and our employers didn’t do their job.”

if healthy individuals start stockpiling surgical masks and high-grade N95 masks, they can also make it harder for health workers to get the resources they need to help on the front lines.

But studies of influenza pandemics have shown that when high-grade N95 masks are not available, surgical masks do protect people a bit more than not wearing masks at all. And when masks are combined with hand hygiene, they help reduce the transmission of infections.

When researchers conducted systematic review of a variety of interventions used during the SARS outbreak in 2003, they found that washing hands more than 10 times daily was 55 percent effective in stopping virus transmission, while wearing a mask was actually more effective — at about 68 percent

Wearing gloves offered about the same amount of protection as frequent hand-washing, and combining all measures — hand-washing, masks, gloves and a protective gown — increased the intervention effectiveness to 91 percent.

Classified data from the Chinese government that was reported in the South China Morning Post indicated that up to a third of all people who tested positive for the coronavirus could have been silent carriers.

Widespread testing on the Diamond Princess showed that half of the positive cases on board the cruise ship had no symptoms.

A new report from the C.D.C., published Friday, also suggests that several residents of a nursing facility in King County, Washington, either did not have any symptoms or developed very mild symptoms only after they had been confirmed to have a coronavirus infection.

“It’s still hard to tell what percentage of people are truly asymptomatic because many go on to develop symptoms a few days later,

“What we do know is that individuals can shed virus about 48 hours before they develop symptoms and masking can prevent transmission from those individuals.”

Wearing a mask can also reduce the likelihood that people will touch their face

In many Asian countries, everyone is encouraged to wear masks, and the approach is about crowd psychology and protection. If everyone wears a mask, individuals protect each other, reducing overall community transmission

The sick automatically have one on and are also more likely to adhere to keeping their mask on because the stigma of wearing one is removed.

Masks are also an important signal that it’s not business as usual during a pandemic

They may also serve as an act of solidarity, showing that all citizens are on board with the precautionary measures needed to bring infections under control.

“If everyone in the community wears a mask, it could decrease transmission,” Dr. Fishman said. “But unfortunately I think that we don’t have enough masks to make that effective policy in the U.S.”

Mr. Biden, the Democratic presidential nominee, echoed the “dark winter” language during the most recent presidential debate, and he is already using his bully pulpit to promote and reinforce a culture of mask wearing.

He could use his authority under federal transit law to require masks on public transportation. He could also prod governors who are resisting mask mandates to at least require masks in public buildings in their states.

Instead of making it about the president’s coercive authority under law it should be about whether the president can support a norm that supports public health, which is in people’s self interest

Experts say there is growing scientific evidence that face masks can considerably reduce the transmission of respiratory viruses like the one that causes Covid-19.

it is time to seriously consider a national mandate to curb the spread of the virus.

the Institute for Health Metrics and Evaluation at the University of Washington estimated that “universal mask use” — when 95 percent of people wear masks in public — could prevent nearly 130,000 deaths from Covid-19 in the coming months, though those numbers are based on certain assumptions and could change if people alter their behavior

any hint of a sweeping federal requirement would “go over like a lead balloon” and “divide and harden areas of the country in opposition,”

that has not produced the kind of compliance that public health experts say is necessary to reduce the spread of the virus

Some public health experts fear that Mr. Trump — who routinely mocks Mr. Biden for wearing masks and whose aides often forgo them even as the White House has become its own coronavirus hot spot — has so poisoned the discussion around masks that wearing them will always be construed as a political statement.

She also suggested that insurance industry executives might be persuaded to adjust their policies to require that businesses mandate mask wearing by customers and employees in order to receive coverage.

“There’s a presumption that a mask mandate would have to be backed up with fines and set off scuffles with law enforcement,

There is some evidence that norms are changing.

This was (and is) America, after all. The government can't tell you what to do! Every individual gets to make their own decisions!

He also repeatedly mocked Joe Biden for wearing a mask during the teeth of the pandemic.

"Did you ever see a man that likes a mask as much as him?" Trump asked a campaign rally crowd in Pennsylvania in September 2020. "And then he makes a speech, and he always has it -- not always, but a lot of times -- he has it hanging down. Because, you know what, it gives him a feeling of security. If I were a psychiatrist -- right? I'd say, this guy's got some big issues. Hanging down."

In May 2020 on a trip to a Ford plant in Michigan, Trump said that he wore a mask away from reporters and cameras, but took it off because he "didn't want to give the press the pleasure of seeing it."

This is (and was) a ridiculous line of thinking when it came to a pandemic. The only way to limit infections -- until the development of the Covid-19 vaccine -- was to stop so many people from getting it.

Not wearing a mask, then, wasn't just about you and your rights. It literally endangered other people.

Anyway, the point here is that Mandel sees his path to the GOP nomination as painting himself as the Trumpiest candidate in the crowded field. And because Trumpism isn't about a set of policy prescriptions but rather focused on tone (owning the libs, mostly), the way to demonstrate fealty to the former President is through stunts like, say, burning a mask.

What's most depressing here -- at least to me -- is that Mandel's transparent ploy will probably work. The video, posted on Tuesday night, already has more than 400,000 views. Trumpists will celebrate it -- and Mandel -- as heroes willing to fight against the nanny state.

But that doesn't matter. Masks are bad because Trump said they were. Which is more than enough justification for Mandel.

Pressed about the dinner in a radio interview in late November, Mr. Gazelka, 61, who is reported to be considering a run for governor, said he had no regrets.

“The idea that everyone can just be trusted rings a little hollow with the knowledge” that Republicans did not tell Democrats of the positive cases before the special session, Ms. Kent said in an interview last week.

He continued through the year to argue that mask mandates or limits on restaurants and bars were not needed because Minnesotans could be trusted to make responsible choices, and that the harmful effects on schools, the economy and people’s mental health outweighed the value of restrictions.

Holding the celebratory dinner wasn’t the only point of contention.Afterward, Republicans alerted their own caucus about the virus outbreak, but not Democrats. They instructed Republican staff members not to go to the Capitol for a special session of the Legislature on Nov. 12 — but did not inform Democrats, who were livid after learning of the positive cases from news reports.

“There was a lot of food and a lot of beverage, and when you’re at an activity when the food and beverage is there, that’s when you don’t have your mask,” he said. “I don’t regret that we had the celebration. The Republican majority was the No. 1 target to switch from Republican to Democrat.”

She described the working environment of the Senate as poisoned by Republicans’ disregard for masks. Most refuse to wear them on the Senate floor, she said. One Republican senator, she recounted, broke into fake coughing while waiting for an elevator in a cramped vestibule with Democratic colleagues.

After learning of the outbreak from Republican leaders, Mr. Relph, who did not have any symptoms, went for a coronavirus test, his daughter said. It came back positive.

“None of us can be sure he got sick at that party, but it’s really, really likely,” Dana Relph said. “There wasn’t any other place he would have gotten it.”

As one of the Senate’s oldest members, Mr. Relph was one of the few Republicans known for regularly wearing a face covering. He had an underlying condition, mild asthma, his daughter said.

As a lab technician for 3M, Ms. Relph tests industrial masks. “The fact that people deny the science behind masks makes me even angrier,” she said. She recalled that a Senate colleague of her father’s had stopped by her family’s house, without a mask, while her father was in the hospital. “Point blank, he said, ‘I don’t think this is as serious as they’re telling us it is,’” Ms. Relph said. “My dad was dying. These are people that think they’re good, kind, compassionate people, and yet they don’t act that way.”

Last week, as the Legislature returned for its 2021 session, senators held a moment of silence for Mr. Relph. Mr. Gazelka called him “a great senator, a true friend.”

The majority leader also led his party in blocking a Democratic proposal to require masks in public areas of the Capitol, flouting a statewide mask mandate, imposed by the governor, in indoor settings. (The Legislature is not subject to the governor’s orders.) Republicans questioned the effectiveness of masks. But Mr. Gazelka did include language in a resolution “strongly encouraging” mask wearing.

Ms. Kent, the Democratic leader, said that she had noticed lately that Mr. Gazelka was always wearing a mask himself in the Capitol, where before he had not worn one. Besides Mr. Relph’s death, Mr. Gazelka’s mother-in-law died in December after contracting Covid-19.

Masks also could reassure people with whom you share paths or sidewalks while running and who, in my experience, have started to shy away when we runners pant by.

Even so, most of us probably should cover our faces while we exercise outside. The Centers for Disease Control and Prevention recommends that everyone now wear a mask of some kind when they leave home

“Running is good for health,” he says, “and transmission risk should be minimal, both for others, if a runner were infected, or for the runner, if they passed by infected people.”

“If the mouth and nose are fully covered,” he says, “there may be some limitation to the intake of air, which may raise discomfort and attenuate your running performance.”

Worse, he says, wet masks “lose antimicrobial efficiency.”

And then there is the oozing. “Exercising in a face mask will create a warm and humid microclimate around your face” as the mask traps your exhaled breaths

the mask turns the bottom half of your face into a “mini-sauna,” he says, leading to a buildup of sweat under the mask and a related rise in nasal secretions.

The result can feel “unpleasant,” he says, if, like so many of us, “you find the sensation of mucus pouring down your face to be unpleasant.”

“The most important precaution is social distancing,” Dr. Boulet says. Stay at least six feet away from anyone you pass. And disinfect your hands and your mask when you get home.

For about a year, major U.S. commercial airlines have required all passengers who are older than 2 to wear face masks on flights.

Just this week, the Centers for Disease Control and Prevention said people who are fully vaccinated do not need to wear a mask when they're outdoors unless they're in a crowd.

According to NPR's vaccine tracker, over 40% of the U.S. population has received their first dose of a COVID-19 vaccine and about 30% is fully vaccinated. CDC data also projects that close to 85% of the country could be fully vaccinated by the end of August.

Travel numbers are also rising. TSA reported that 1.56 million people traveled through airport checkpoints on Friday, compared with about 171,000 on the same day in 2020.

At the beginning of April, the CDC announced that Americans who are fully vaccinated can safely travel in the U.S. while still wearing a mask and social distancing. The guidance specifically notes that nonessential travel should continue to be avoided when possible.

India is the latest country to face heightened restrictions from the U.S., following a continuing surge of COVID-19 cases throughout the country. The ban on travelers from India is set to officially take effect Tuesday.

what the administration should have been doing in January to prepare us for today.

She cites the delay on tests, without which “cases go undetected and people continue to circulate” as a leading issue along with other missed federal government responses—many of which are still not fully operational

The prescient recommendations from experts across disciplines in the period before COVID-19 reached American shores—about testing, equipment, and distancing—make clear that more than any single factor, it was Trump’s squandering of out lead-time which should have been used to prepare for the pandemic that has exacerbated this crisis.

What follows is an annotated timeline revealing the warning signs the administration received and showing how slow the administration was to act on these recommendations.

The Early Years: Warnings Ignored

2017: Trump administrations officials are briefed on an intelligence document titled “Playbook for Early Response to High-Consequence Emerging Infectious Disease Threats and Biological Incidents.” That’s right. The administration literally had an actual playbook for what to do in the early stages of a pandemic

February 2018: The Washington Post writes “CDC to cut by 80 percent efforts to prevent global disease outbreak.” The meat of the story is “Countries where the CDC is planning to scale back include some of the world’s hot spots for emerging infectious disease, such as China, Pakistan, Haiti, Rwanda and Congo.”

May 2018: At an event marking the 100 year anniversary of the 1918 pandemic, Borio says “pandemic flu” is the “number 1 health security issue” and that the U.S. is not ready to respond.

One day later her boss, Rear Adm. Timothy Ziemer is pushed out of the administration and the global health security team is disbanded

Beth Cameron, former senior director for global health security on the National Security Council adds: “It is unclear in his absence who at the White House would be in charge of a pandemic,” Cameron said, calling it “a situation that should be immediately rectified.” Note: It was not

January 2019: The director of National Intelligence issues the U.S. Intelligence Community’s assessment of threats to national security. Among its findings:

A novel strain of a virulent microbe that is easily transmissible between humans continues to be a major threat, with pathogens such as H5N1 and H7N9 influenza and Middle East Respiratory Syndrome Coronavirus having pandemic potential if they were to acquire efficient human-to-human transmissibility.”

Page 21: “We assess that the United States and the world will remain vulnerable to the next flu pandemic or large scale outbreak of a contagious disease that could lead to massive rates of death and disability, severely affect the world economy, strain international resources, and increase calls on the United States for support.”

September, 2019: The Trump Administration ended the pandemic early warning program, PREDICT, which trained scientists in China and other countries to identify viruses that had the potential to turn into pandemics. According to the Los Angeles Times, “field work ceased when funding ran out in September,” two months before COVID-19 emerged in Wuhan Province, China.

2020: COVID-19 Arrives

anuary 3, 2020: The CDC is first alerted to a public health event in Wuhan, China

January 6, 2020: The CDC issues a travel notice for Wuhan due to the spreading coronavirus

Note: The Trump campaign claims that this marks the beginning of the federal government disease control experts becoming aware of the virus. It was 10 weeks from this point until the week of March 16 when Trump began to change his tone on the threat.

January 10, 2020: Former Trump Homeland Security Advisor Tom Bossert warns that we shouldn’t “jerk around with ego politics” because “we face a global health threat…Coordinate!”

January 18, 2020: After two weeks of attempts, HHS Secretary Alex Azar finally gets the chance to speak to Trump about the virus. The president redirects the conversation to vaping, according to the Washington Post. 

January 21, 2020: Dr. Nancy Messonnier, the director of the National Center for Immunization and Respiratory Disease at the CDC tells reporters, “We do expect additional cases in the United States.”

January 27, 2020: Top White House aides meet with Chief of Staff Mick Mulvaney to encourage greater focus on the threat from the virus. Joe Grogan, head of the White House Domestic Policy Council warns that “dealing with the virus was likely to dominate life in the United States for many months.”

January 28, 2020: Two former Trump administration officials—Gottlieb and Borio—publish an op-ed in the Wall Street Journal imploring the president to “Act Now to Prevent an American Epidemic.” They advocate a 4-point plan to address the coming crisis:

(1) Expand testing to identify and isolate cases. Note: This did not happen for many weeks. The first time more than 2,000 tests were deployed in a single day was not until almost six weeks later, on March 11.

(3) Prepare hospital units for isolation with more gowns and masks. Note: There was no dramatic ramp-up in the production of critical supplies undertaken. As a result, many hospitals quickly experienced shortages of critical PPE materials. Federal agencies waited until Mid-March to begin bulk orders of N95 masks.

January 29, 2020: Trump trade advisor Peter Navarro circulates an internal memo warning that America is “defenseless” in the face of an outbreak which “elevates the risk of the coronavirus evolving into a full-blown pandemic, imperiling the lives of millions of Americans.”

January 30, 2020: Dr. James Hamblin publishes another warning about critical PPE materials in the Atlantic, titled “We Don’t Have Enough Masks.”

January 29, 2020: Republican Senator Tom Cotton reaches out to President Trump in private to encourage him to take the virus seriously.

Late January, 2020:  HHS sends a letter asking to use its transfer authority to shift $136 million of department funds into pools that could be tapped for combating the coronavirus. White House budget hawks argued that appropriating too much money at once when there were only a few U.S. cases would be viewed as alarmist.

Trump’s Chinese travel ban only banned “foreign nationals who had been in China in the last 14 days.” This wording did not—at all—stop people from arriving in America from China. In fact, for much of the crisis, flights from China landed in America almost daily filled with people who had been in China, but did not fit the category as Trump’s “travel ban” defined it.

January 31, 2020: On the same day Trump was enacting his fake travel ban, Foreign Policy reports that face masks and latex gloves are sold out on Amazon and at leading stores in New York City and suggests the surge in masks being sold to other countries needs “refereeing” in the face of the coming crisis.

February 4, 2020: Gottlieb and Borio take to the WSJ again, this time to warn the president that “a pandemic seems inevitable” and call on the administration to dramatically expand testing, expand the number of labs for reviewing tests, and change the rules to allow for tests of people even if they don’t have a clear known risk factor.

Note: Some of these recommendations were eventually implemented—25 days later.

February 5, 2020: HHS Secretary Alex Azar requests $2 billion to “buy respirator masks and other supplies for a depleted federal stockpile of emergency medical equipment.” He is rebuffed by Trump and the White House OMB who eventually send Congress a $500 million request weeks later.

February 4 or 5, 2020: Robert Kadlec, the assistant secretary for preparedness and response, and other intelligence officials brief the Senate Intelligence Committee that the virus poses a “serious” threat and that “Americans would need to take actions that could disrupt their daily lives.”

February 5, 2020: Senator Chris Murphy tweets: Just left the Administration briefing on Coronavirus. Bottom line: they aren't taking this seriously enough. Notably, no request for ANY emergency funding, which is a big mistake. Local health systems need supplies, training, screening staff etc. And they need it now.

February 9, 2020: The Washington Post reports that a group of governors participated in a jarring meeting with Dr. Anthony Fauci and Dr. Robert Redfield that was much more alarmist than what they were hearing from Trump. “The doctors and the scientists, they were telling us then exactly what they are saying now,” Maryland Gov. Larry Hogan (R) said.

the administration lifted CDC restrictions on tests. This is a factually true statement. But it elides that fact that they did so on March 3—two critical weeks after the third Borio/Gottlieb op-ed on the topic, during which time the window for intervention had shrunk to a pinhole.

February 20, 2020: Borio and Gottlieb write in the Wall Street Journal that tests must be ramped up immediately “while we can intervene to stop spread.”

February 23, 2020: Harvard School of Public Health professor issues warning on lack of test capability: “As of today, the US remains extremely limited in#COVID19 testing. Only 3 of ~100 public health labs haveCDC test kits working and CDC is not sharing what went wrong with the kits. How to know if COVID19 is spreading here if we are not looking for it.

February 24, 2020: The Trump administration sends a letter to Congress requesting a small dollar amount—between $1.8 billion and $2.5 billion—to help combat the spread of the coronavirus. This is, of course, a pittance

February 25, 2020: Messonier says she expects “community spread” of the virus in the United States and that “disruption to everyday life might be severe.” Trump is reportedly furious and Messonier’s warnings are curtailed in the ensuing weeks.

Trump mocks Congress in a White House briefing, saying “If Congress wants to give us the money so easy—it wasn’t very easy for the wall, but we got that one done. If they want to give us the money, we’ll take the money.”

February 26, 2020: Congress, recognizing the coming threat, offers to give the administration $6 billion more than Trump asked for in order to prepare for the virus.

February 27, 2020: In a leaked audio recording Sen. Richard Burr, chairman of the Intelligence Committee and author of the Pandemic and All-Hazards Preparedness Act (PAHPA) and the Pandemic and All-Hazards Preparedness and Advancing Innovation Act (reauthorization of PAHPA), was telling people that COVID-19 “is probably more akin to the 1918 pandemic.”

March 4, 2020: HHS says they only have 1 percent of respirator masks needed if the virus became a “full-blown pandemic.”

March 3, 2020: Vice President Pence is asked about legislation encouraging companies to produce more masks. He says the Trump administration is “looking at it.”

March 7, 2020: Fox News host Tucker Carlson, flies to Mar-a-Lago to implore Trump to take the virus seriously in private rather than embarrass him on TV. Even after the private meeting, Trump continued to downplay the crisis

March 9, 2020: Tom Bossert, Trump’s former Homeland Security adviser, publishes an op-ed saying it is “now or never” to act. He advocates for social distancing and school closures to slow the spread of the contagion.

Trump says that developments are “good for the consumer” and compares COVID-19 favorably to the common flu.

March 17, 2020: Facing continued shortages of the PPE equipment needed to prevent healthcare providers from succumbing to the virus, Oregon Senators Jeff Merkeley and Ron Wyden call on Trump to use the Defense Production Act to expand supply of medical equipment

March 18, 2020: Trump signs the executive order to activate the Defense Production Act, but declines to use it

At the White House briefing he is asked about Senator Chuck Schumer’s call to urgently produce medical supplies and ventilators. Trump responds: “Well we’re going to know whether or not it’s urgent.” Note: At this point 118 Americans had died from COVID-19.

March 20, 2020: At an April 2nd White House Press Conference, President Trump’s son-in-law Jared Kushner who was made ad hoc point man for the coronavirus response said that on this date he began working with Rear Admiral John Polowczyk to “build a team” that would handle the logistics and supply chain for providing medical supplies to the states. This suggestion was first made by former Trump Administration officials January 28th

March 22, 2020: Six days after calling for a 15-day period of distancing, Trump tweets that this approach “may be worse than the problem itself.”

March 24, 2020: Trump tells Fox News that he wants the country opened up by Easter Sunday (April 12)

As Trump was speaking to Fox, there were 52,145 confirmed cases in the United States and the doubling time for daily new cases was roughly four days.

In liberal enclaves, where public support for masking has generally been high, many customers continue to wear masks whether or not they are required.

That compared with only 71 percent of Republicans who said they wore a mask outside the home at least most of the time, and just half said they thought masks were effective.

Vaccinated guests are allowed to walk around without masks, but there is no way to verify vaccination status and fewer than half of guests are wearing them, according to Mr. Kennon.

“Security won’t ask them to show a vaccine card,” he said. “It’s certainly stressful amongst my co-workers.”

By contrast, in Bethesda, Md., in a county where the vast majority voted for President Biden, mask-wearing appears to be largely unaffected by the C.D.C. shift.

“We had people walking in, not buying anything, just chewing gum with their mouths open — a ‘see if anyone stops me’ kind of dance,’” said Mr. Mason

“Many employers are following state guidance, which is throwing public health precautions out the window.”

A White House official acknowledged that it was reviewing the proposal but declined to comment further.

Yet a feared spike in cases and deaths has not materialized. Japan has reported more than 17,000 infections and just over 900 deaths, while the United States, with a population roughly two and a half times as large, is approaching 1.9 million cases and 110,000 deaths.

Japan, I think a lot of people agree, kind of did everything wrong, with poor social distancing, karaoke bars still open and public transit packed near the zone where the worst outbreaks were happening,” Jeremy Howard, a researcher at the University of San Francisco who has studied the use of masks, said of the country’s early response. “But the one thing that Japan did right was masks.”

one of Japan’s most visible responses has been near-universal mask wearing, seen here as a responsible thing to do to protect oneself and others, and as a small price to pay to be able to resume some semblance of normalcy.

Dr. Onishi said that early in the 20th century, the Japanese viewed masks as unattractive, but were persuaded to wear them during the 1918 flu pandemic. More recently, the Japanese public has used masks during the SARS and MERS outbreaks — which also left Japan relatively unscathed — as well as to protect against pollution and pollen.

During the current pandemic, scientists have found a correlation between high levels of mask-wearing — whether as a matter of culture or policy — and success in containing the virus.

“I think there is definitely evidence coming out of Covid that Japan, as well as other countries which practice mask-wearing, tend to do much better in flattening the curve,” said Akiko Iwasaki, a professor of immunobiology at Yale.

The scientific evidence on whether a mask protects the wearer from infection is mixed. But experiments show that masks can be effective in blocking the emission of respiratory droplets that may contain the virus, even when someone has no symptoms of illness. And there is some evidence that infected people with no symptoms can still transmit the coronavirus.

In no other high-income country — and in only a few countries, period — have political leaders departed from expert advice as frequently and significantly as the Trump administration. President Trump has said the virus was not serious; predicted it would disappear; spent weeks questioning the need for masks; encouraged states to reopen even with large and growing caseloads; and promoted medical disinformation.

many agree that the poor results in the United States stem in substantial measure from the performance of the Trump administration.

“As an American, I think there is a lot of good to be said about our libertarian tradition,” Dr. Jared Baeten, an epidemiologist and vice dean at the University of Washington School of Public Health, said. “But this is the consequence — we don’t succeed as well as a collective.”

That tradition is one reason the United States suffers from an unequal health care system that has long produced worse medical outcomes — including higher infant mortality and diabetes rates and lower life expectancy — than in most other rich countries.

First, the United States faced longstanding challenges in confronting a major pandemic. It is a large country at the nexus of the global economy, with a tradition of prioritizing individualism over government restrictions.

The New York Times set out to reconstruct the unique failure of the United States, through numerous interviews with scientists and public health experts around the world. The reporting points to two central themes.

When it comes to the virus, the United States has come to resemble not the wealthy and powerful countries to which it is often compared but instead far poorer countries, like Brazil, Peru and South Africa, or those with large migrant populations, like Bahrain and Oman.

That’s more than five times as many as in all of Europe, Canada, Japan, South Korea and Australia, combined.

Over the past month, about 1.9 million Americans have tested positive for the virus.

one country stands alone, as the only affluent nation to have suffered a severe, sustained outbreak for more than four months: the United States.

Nearly every country has struggled to contain the coronavirus and made mistakes along the way.

it quickly became clear that the United States’ policy was full of holes. It did not apply to immediate family members of American citizens and permanent residents returning from China, for example. In the two months after the policy went into place, almost 40,000 people arrived in the United States on direct flights from China.

On Jan. 31, his administration announced that it was restricting entry to the United States from China: Many foreign nationals — be they citizens of China or other countries — would not be allowed into the United States if they had been to China in the previous two weeks.

A travel policy that fell short

In retrospect, one of Mr. Trump’s first policy responses to the virus appears to have been one of his most promising.

The administration’s policy also did little to create quarantines for people who entered the United States and may have had the virus.

ven more important, the policy failed to take into account that the virus had spread well beyond China by early February. Later data would show that many infected people arriving in the United States came from Europe

South Korea, Hong Kong and Taiwan largely restricted entry to residents returning home. Those residents then had to quarantine for two weeks upon arrival

South Korea and Hong Kong also tested for the virus at the airport and transferred anyone who was positive to a government facility.

“People need a bit more than a suggestion to look after their own health,” said Dr. Mackay, who has been working with Australian officials on their pandemic response. “They need guidelines, they need rules — and they need to be enforced.”

Travel restrictions and quarantines were central to the success in controlling the virus in South Korea, Hong Kong, Taiwan and Australia, as well as New Zealand, many epidemiologists believe. In Australia, the number of new cases per day fell more than 90 percent in April. It remained near zero through May and early June, even as the virus surged across much of the United States.

the tolls in Australia and the United States remain vastly different. Fewer than 300 Australians have died of complications from Covid-19, the illness caused by the virus. If the United States had the same per capita death rate, about 3,300 Americans would have died, rather than 158,000.

there is a good chance that a different version of Mr. Trump’s restrictions — one with fewer holes and stronger quarantines — would have meaningfully slowed the virus’s spread.

travel restrictions had been successful enough in fighting the coronavirus around the world that those views may need to be revisited.“Travel,” he said, “is the hallmark of the spread of this virus around the world.”

Traditionally, public health experts had not seen travel restrictions as central to fighting a pandemic, given their economic costs and the availability of other options, like testing, quarantining and contact tracing

But he added that

By early March, with the testing delays still unresolved, the New York region became a global center of the virus — without people realizing it until weeks later. More widespread testing could have made a major difference, experts said, leading to earlier lockdowns and social distancing and ultimately less sickness and death.

While the C.D.C. was struggling to solve its testing flaws, Germany was rapidly building up its ability to test. Chancellor Angela Merkel, a chemist by training, and other political leaders were watching the virus sweep across northern Italy, not far from southern Germany, and pushed for a big expansion of testing.

By the time the virus became a problem in Germany, labs around the country had thousands of test kits ready to use. From the beginning, the government covered the cost of the tests. American laboratories often charge patients about $100 for a test.

Without free tests, Dr. Hendrik Streeck, director of the Institute of Virology at the University Hospital Bonn, said at the time, “a young person with no health insurance and an itchy throat is unlikely to go to the doctor and therefore risks infecting more people.”

Germany was soon far ahead of other countries in testing. It was able to diagnose asymptomatic cases, trace the contacts of new patients and isolate people before they could spread the virus. The country has still suffered a significant outbreak. But it has had many fewer cases per capita than Italy, Spain, France, Britain or Canada — and about one-fifth the rate of the United States.

One measure of the continuing troubles with testing is the percentage of tests that come back positive. In a country that has the virus under control, fewer than 5 percent of tests come back positive, according to World Health Organization guidelines. Many countries have reached that benchmark. The United States, even with the large recent volume of tests, has not.

In Belgium recently, test results have typically come back in 48 to 72 hours. In Germany and Greece, it is two days. In France, the wait is often 24 hours.

The conflicting advice, echoed by the C.D.C. and others, led to relatively little mask wearing in many countries early in the pandemic. But several Asian countries were exceptions, partly because they had a tradition of mask wearing to avoid sickness or minimize the effects of pollution.

The double mask failure

By January, mask wearing in Japan was widespread, as it often had been during a typical flu season. Masks also quickly became the norm in much of South Korea, Thailand, Vietnam, Taiwan and China.

In the following months, scientists around the world began to report two strands of evidence that both pointed to the importance of masks: Research showed that the virus could be transmitted through droplets that hang in the air, and several studies found that the virus spread less frequently in places where people were wearing masks.

the 10 countries with the highest deaths per capita were all in Latin America or the Caribbean.

deep-seated skepticism among people like Mr. Arriaga — the workers who feed Mexico City and much of the nation — turned to shock, and eventually to resignation, as their neighbors, friends and loved ones died and their neighborhood became ground zero for the outbreak.

Officials had posted signs warning of Covid-19 and urging workers to report illnesses. In the beginning, most ignored them.“I think they made it up, to raise prices on the poor,” Mr. Arriaga said of the virus in March

A new reality set in for many: A prolonged economic shutdown was clearly impossible. People could wear masks, and distance as much as possible, but almost no one could afford to stay home. They had to keep working.

For the vast majority of people, risking illness or death has simply become the price of survival.

Mr. Arriaga’s own attempts to stay away from the market lasted only a month before he blew through his life savings and trudged back to work in fear.“I’ve got nothing left,” he said on a recent weekend, bracing himself for another long night in the market. “It’s either go out there and face the virus, or sit here and starve.”

Now, Mexico has the fourth-highest death toll in the world, with more than 70,000 lives officially lost to the virus. Experts say the real number may be tens of thousands more than that.

Tomas BravoMexico City8h agoGreat article. Even living in the same city there are different realities playing out, and this gives a good insight into the stories of some of the worst struck by the pandemic. Some local media have talked of these issues, but there is an ongoing effort from the government to deny these allegations. It is nice to see a story told from the perspective of individuals through which the bigger issues that have paved the way for this crisis are highlighted

(b) we see no arguments about mask wearing in CDMX stores/areas, and witnessed concerns about customers shooting up USA grocery stories if masks are enforced,

gtodonGuanajuato, Mexico3h ago@Ignacio Colin Perhaps in your neighborhood of sprawling Mexico City, the "community is strong and doing its part." Where I live, in Guanajuato, about half the people on the streets, and even in the stores, decline to wear masks, and half of those who do wear masks don't wear them properly; they appear to think they're chin-guards. The same is true in nearby León, a much larger city. In the state of Guanajuato, only San Miguel de Allende, with its large foreign population, takes Covid seriously.

BVINew York7h agoPowerful article with powerful images. I felt close to the shopkeepers and their families. The intimacy of these stories and revealing personal impact in such detail, without judgment, makes the story so much more human. "At every level, there is simply less." A sadly perfect summation of this pandemic's impact.

IvanMemphis, TN9h agoTwo failures seem to be conspiring to make this a catastrophe. First the governments failure to institute simple low cost and effective measures to reduce the spreed - like mandatory and enforced masks in crowded public areas. Second the failure of the public to take it serious and follow common sense guidance - because of paranoia about the motives of experts and government. I guess they are not that different from the US, except they have less resources to counter the predictable outcomes of these failures.

gnacio ColinMexico City8h agoOnce again, we are portrayed as a country that diminishes the virus’ impact and downplays it. It’s a great read but tbh most of the responsibility lays on the President, who has been adamant about employing techniques that do not combat the virus. Nonetheless, Mexico City’s government led by a PhD, Claudia Sheinbaum has done a great job and has countered the President in many ways regarding the management. We have a dormant President who chooses to look elsewhere instead of looking for solutions (he’s done the same with medication purchases, education, ecology, human rights commissions, to say the least). The Mexican community is strong and is doing its part on mitigating this national (and global) tragedy.

D. HendersonMexico City4h ago@Jorge Romero and @ E. Voigt, you have points and they are well taken. I live in CMDX and work in rural MX. In July, we made a "necessary" risky cross-country drive to see Ohio family b/c we suspect that such is impossible until a vaccine in spring 2021 or later. We used masks, face shields, alcohol solutions when at two hotels & gas stations. Some anectodal sharing

Like many people in Iztapalapa, they felt a sense of shame associated with the virus.“There’s a stigma,” said Mr. Dominguez, the organizer. “No one wants to admit they had it.”

ExPatMXAjijic, Jalisco Mexico7h ago@observer " We shouldn't be reporting on these "poor countries" as if we are so far removed on our American pedestal any longer." Thank you. Mexico is a magnificent country and the people remind me of how Americans treated each other with kindness and friendliness when I was young. They make eye contact on the streets, wish you a good day, you'll see teenage boys taking young siblings places with care and loving. There are some places in the US that this happens but a lot more places that it doesn't. Is the government corrupt? Certainly. But they are open about it while the US government is equally corrupt but hides it behind religion or other convenient excuses. We have been adopted" into a few Mexican families and attend birthdays, wedding, and fiestas. This article made me want to cry. The poor in Mexico are struggling to survive just as the poor in the US are similarly struggling. This article put faces on the essential workers who are risking their lives to feed their families (and the rest of the country) which I think is needed so the rest of us who are lucky can identify with what this disease is doing to people.

(c) CDMX is MASSIVE, centro de abastos is massive, hard to relay really its size and diversity and intensity. It IS "formally" and "informally" opening up again for many of the reasons explained in this article; it "feels" like a deal is being made with the COVID-19 devil (only time and the virus will dictate outcomes).

ONE. Thank you NYT for this article and to the commentators for their sharing. Good. TWO. When comparing citizen behavior in CDMX streets to what we saw in TX, TN, AR, KY, OH we note (a) NOW 95-100% of people in CDMX streets, metro, tianguis (markets) use masks, compared with 40-50% (or less depending on USA area),

PaulRio de Janeiro10h agoI cannot speak for Mexico, but I can speak for Brazil, where many cities have seen their numbers plummet, sometimes by over 90%. This is the case in Rio where much has been open for weeks, months in the case of malls and many other public places, without dire consequences.

At this very moment I personally know more people sick in Europe than I do here in Rio or even in Brazil. This is not to minimize the impact that Covid had on Latin America, on Brazil and on Rio. The opposite in fact: it is close to undeniable that some measure of herd immunity was attained in many of the hardest hit places, including New York City, northern Italy and several Brazilian cities.

d) urban CDMX life is different than rural MX life (and other MX cities) always and now; yet, there is a general lack of trust across the board about info and institutions, so much so that we know the death rate IS not accurate, many die in their homes rather than go to hospitals). Survive is what we all must do.

The recovery of places like Manaus, Recife, Rio, São Paulo and other Brazilian cities has been woefully underreported by the New York Times and others. It is too bad because an analysis of the data and of the facts on the ground could yield valuable insight for other countries and cities, especially in poor or emerging countries.

misinformation was as rampant as the virus itself.Ms. Aquino’s cellphone brimmed with clips sent via WhatsApp. Some claimed that the virus was a Chinese conspiracy, others that bleach was a cure. Even President Andrés Manuel López Obrador offered his own theories, contending that a clean conscience helped prevent infection.

“I’ve heard government is paying people to claim their loved ones died from Covid,” Ms. Aquino whispered. “I have two friends who were offered money.”At best, the rumors sowed confusion and doubt. At worst, they were a death sentence.

A dull acceptance of the new reality filled Iztapalapa: Coronavirus is a necessary risk, and the reward for taking it is merely survival.

Thank you for this story about our new home country. We live far from Mexico City in the state of Jalisco where the governor and local officials took the virus seriously. So far their efforts have been rewarded with per capita numbers of cases around 20 per 100,000, some of the consistently best results anywhere in the world.

I was born and raised in Mexico and all my family is still there. Back in March I received video in which a central de abastos worker mocks the pandemic and people who are quarantining calling them lazy, and those wearing masks, gullible. The video to me helped illustrate the hard truth that México, like the USA, has parallel narratives. There are those who believe the science and consume fact-checked news, like my relatives. And there are also many who believe conspiracy theories or folk remedies, including misinformation on YouTube. I believe the official tally of the sick and dead is much lower than the real numbers. This disease is exposing the fragility of Mexico’s institutions, much like it has American ones.

As a full-time resident of Mexico I can attest that most Mexicans either have had a family member ill from Covid and/or have lost a family member to Covid. It has attacked not only low income but also middle and upper classes. It is rampant here but unfortunately the wealthy have better access to adequate health care. Most Mexicans I know are very vigilant about mask wearing; unfortunately the American tourists who come to holiday here are not vigilant and are reluctant to wear masks.

ilToronto

Rachael EiermannLos Cabos, Mexico

Brad BurnsMexico

It’s not just political factions using the issue for partisan advantage – though that is happening as Covid-19 restrictions continue to straddle the quintessentially American tension between individual freedom and the reach of government. Medical experts are engaging in an intense debate over whether the CDC is being too cautious in the way it’s loosening mask guidance or is offering the public conflicting, confusing advice.

The complications of exiting the pandemic – a process that no one currently in positions of power has ever experienced – explain why Biden’s success in getting more than 100 million Americans fully immunized doesn’t mean Covid-19 is no longer perilous or is any less politically treacherous for the White House.

The President’s remarks followed new CDC guidance last week that mean fully vaccinated people can now unmask at small outdoor gatherings or when dining outside with friends from multiple households. Unvaccinated people should still cover their faces.

The Republican National Committee, for instance, blasted Biden for “breaking” US Centers for Disease Control and Prevention guidance, and the issue has become one of the latest culture war flashpoints for right-wing talk show hosts.

“It’s time for the CDC to start embracing this kind of bifurcated strategy and perhaps giving the unvaccinated a hint of what life can be like if they become vaccinated,” he said.

This is a pretty dangerous time to be unvaccinated, but what (the) CDC is signaling is if you are fully vaccinated, freedoms are just becoming safer and safer for people.”

While public health experts warn that maximizing vaccinations is vital to creating the herd immunity in the population necessary to stop Covid-19 spreading

“It is America. Everybody has an individual right. I think that one of the things we have to be careful about is not shaming people or talking down to them or objecting to their way of life,” Marshall told CNN’s Pamela Brown on “Newsroom” on Saturday.

They’ve been told they don’t need a mask. They need a mask. They’ve been told that even if you have a vaccine, you have to keep wearing the mask,” Marshall said.

the best way to ease such concerns and to get rid of masks for good is to get vaccinated.

“My first and biggest wish is that we had known early that Covid-19 was airborne,”

, “Once you’ve realized that, it informs an entirely different strategy for protection.” Masking, ventilation and air cleaning become key, as well as avoiding high-risk encounters with strangers, he says.

Instead of washing our produce and wearing hand-sewn cloth masks, we could have made sure to avoid superspreader events and worn more-effective N95 masks or their equivalent. “We could have made more of an effort to develop and distribute N95s to everyone,” says Dr. Volckens. “We could have had an Operation Warp Speed for masks.”

We didn’t realize how important clear, straight talk would be to maintaining public trust. If we had, we could have explained the biological nature of a virus and warned that Covid-19 would change in unpredictable ways.  

In the face of a pandemic, he says, the public needs an early basic and blunt lesson in virology

“The science is really important, but if you don’t get the trust and communication right, it can only take you so far,”

and mutates, and since we’ve never seen this particular virus before, we will need to take unprecedented actions and we will make mistakes, he says.

Since the public wasn’t prepared, “people weren’t able to pivot when the knowledge changed,”

By the time the vaccines became available, public trust had been eroded by myriad contradictory messages—about the usefulness of masks, the ways in which the virus could be spread, and whether the virus would have an end date.

, the absence of a single, trusted source of clear information meant that many people gave up on trying to stay current or dismissed the different points of advice as partisan and untrustworthy.

We didn’t know how difficult it would be to get the basic data needed to make good public-health and medical decisions. If we’d had the data, we could have more effectively allocated scarce resources

For much of the pandemic, doctors, epidemiologists, and state and local governments had no way to find out in real time how many people were contracting Covid-19, getting hospitalized and dying

Doctors didn’t know what medicines worked. Governors and mayors didn’t have the information they needed to know whether to require masks. School officials lacked the information needed to know whether it was safe to open schools.

people didn’t know whether it was OK to visit elderly relatives or go to a dinner party.

just months before the outbreak of the pandemic, the Council of State and Territorial Epidemiologists released a white paper detailing the urgent need to modernize the nation’s public-health system still reliant on manual data collection methods—paper records, phone calls, spreadsheets and faxes.

While the U.K. and Israel were collecting and disseminating Covid case data promptly, in the U.S. the CDC couldn’t. It didn’t have a centralized health-data collection system like those countries did, but rather relied on voluntary reporting by underfunded state and local public-health systems and hospitals.

doctors and scientists say they had to depend on information from Israel, the U.K. and South Africa to understand the nature of new variants and the effectiveness of treatments and vaccines. They relied heavily on private data collection efforts such as a dashboard at Johns Hopkins University’s Coronavirus Resource Center that tallied cases, deaths and vaccine rates globally.

With good data, Dr. Ranney says, she could have better managed staffing and taken steps to alleviate the strain on doctors and nurses by arranging child care for them.

To solve the data problem, Dr. Ranney says, we need to build a public-health system that can collect and disseminate data and acts like an electrical grid. The power company sees a storm coming and lines up repair crews.

If we’d known how damaging lockdowns would be to mental health, physical health and the economy, we could have taken a more strategic approach to closing businesses and keeping people at home.

t many doctors say they were crucial at the start of the pandemic to give doctors and hospitals a chance to figure out how to accommodate and treat the avalanche of very sick patients.

The measures reduced deaths, according to many studies—but at a steep cost.

The lockdowns didn’t have to be so harmful, some scientists say. They could have been more carefully tailored to protect the most vulnerable, such as those in nursing homes and retirement communities, and to minimize widespread disruption.

Lockdowns could, during Covid-19 surges, close places such as bars and restaurants where the virus is most likely to spread, while allowing other businesses to stay open with safety precautions like masking and ventilation in place.  

If England’s March 23, 2020, lockdown had begun one week earlier, the measure would have nearly halved the estimated 48,600 deaths in the first wave of England’s pandemic

If the lockdown had begun a week later, deaths in the same period would have more than doubled

The key isn’t to have the lockdowns last a long time, but that they are deployed earlier,

It is possible to avoid lockdowns altogether. Taiwan, South Korea and Hong Kong—all countries experienced at handling disease outbreaks such as SARS in 2003 and MERS—avoided lockdowns by widespread masking, tracking the spread of the virus through testing and contact tracing and quarantining infected individuals.

Had we known that even a mild case of Covid-19 could result in long Covid and other serious chronic health problems, we might have calculated our own personal risk differently and taken more care.

Early in the pandemic, public-health officials were clear: The people at increased risk for severe Covid-19 illness were older, immunocompromised, had chronic kidney disease, Type 2 diabetes or serious heart conditions

t had the unfortunate effect of giving a false sense of security to people who weren’t in those high-risk categories. Once case rates dropped, vaccines became available and fear of the virus wore off, many people let their guard down, ditching masks, spending time in crowded indoor places.

it has become clear that even people with mild cases of Covid-19 can develop long-term serious and debilitating diseases. Long Covid, whose symptoms include months of persistent fatigue, shortness of breath, muscle aches and brain fog, hasn’t been the virus’s only nasty surprise

In February 2022, a study found that, for at least a year, people who had Covid-19 had a substantially increased risk of heart disease—even people who were younger and had not been hospitalized

respiratory conditions.

Some scientists now suspect that Covid-19 might be capable of affecting nearly every organ system in the body. It may play a role in the activation of dormant viruses and latent autoimmune conditions people didn’t know they had

 A blood test, he says, would tell people if they are at higher risk of long Covid and whether they should have antivirals on hand to take right away should they contract Covid-19.

If the risks of long Covid had been known, would people have reacted differently, especially given the confusion over masks and lockdowns and variants? Perhaps. At the least, many people might not have assumed they were out of the woods just because they didn’t have any of the risk factors.

“A warped freedom obsession is killing us,” said the writer Anand Giridharadas, in reference to those coughing in the faces of others in the name of freedom

It is, of course, a minority of people willfully misinterpreting what freedom means – freedom to choose, until the choice is one that they do not like

In Franklin D Roosevelt’s famous 1941 Four Freedoms speech, he detailed that, yes, Americans are owed a right to freedom of speech and expression and to worship whom they please – but he also mentioned the freedom from fear

The World Health Organization and the Centers for Disease Control and Prevention continue to state that masks don’t necessarily protect healthy individuals from getting infected as they go about their daily lives.

While wearing a mask may not necessarily prevent healthy people from getting sick, and it certainly doesn’t replace important measures such as hand-washing or social distancing, it may be better than nothing, Dr. Atmar said.

The official guidance continues to recommend that masks should be reserved for people who are already sick,

“The swift increase in cases to these levels in the U.S. highlights to an even greater degree the importance of implementing and adhering to public health measures,”

the recent surge in infections in the United States, which has put the country at the center of the epidemic, with more confirmed cases than China,

But studies of influenza pandemics have shown that when high-grade N95 masks are not available, surgical masks do protect people a bit more than not wearing masks at all.

With the current coronavirus, researchers are also finding that there are more asymptomatic cases than were known early on in the pandemic.

“It’s still hard to tell what percentage of people are truly asymptomatic because many go on to develop symptoms a few days later,” said Dr. Neil Fishman, the chief medical officer of the Hospital of the University of Pennsylvania.

A month later, I believe that the transmission of SARS-CoV-2 via aerosols matters much more than has been officially acknowledged to date.

This confirms the results of a study from late May (not peer-reviewed) in which Covid-19 patients were found to release SARS-CoV-2 simply by exhaling — without coughing or even talking. The authors of that study said the finding implied that airborne transmission “plays a major role” in spreading the virus.

Accepting these conclusions wouldn’t much change what is currently being recommended as best behavior. The strongest protection against SARS-CoV-2, whether the virus is mostly contained in droplets or in aerosols, essentially remains the same: Keep your distance and wear masks.

Rather, the recent findings are an important reminder to also be vigilant about opening windows and improving airflow indoors. And they are further evidence that the quality of masks and their fit matter, too.

here is no neat and no meaningful cutoff point — at 5 microns or any other size — between droplets and aerosols: All are tiny specks of liquid, their size ranging along a spectrum that goes from very small to really microscopic.

Yes, droplets tend to fly through the air like mini cannonballs and they fall to the ground rather quickly, while aerosols can float around for many hours.

The practical implications are plain:Social distancing really is important. It keeps us out of the most concentrated parts of other people’s respiratory plumes. So stay away from one another by one or two meters at least — though farther is safer.

“The smaller the exhaled droplets, the more important the short-range airborne route.”

Can you walk into an empty room and contract the virus if an infected person, now gone, was there before you? Perhaps, but probably only if the room is small and stuffy.

Can the virus waft up and down buildings via air ducts or pipes? Maybe, though that hasn’t been established.

another, recent, preprint (not peer reviewed) about the Diamond Princess concluded that “aerosol inhalation was likely the dominant contributor to Covid-19 transmission” among the ship’s passengers.

It might seem logical, or make intuitive sense, that larger droplets would contain more virus than do smaller aerosols — but they don’t.

The Lancet Respiratory Medicine that analyzed the aerosols produced by the coughs and exhaled breaths of patients with various respiratory infections found “a predominance of pathogens in small particles” (under 5 microns). “There is no evidence,” the study also concluded, “that some pathogens are carried only in large droplets.”

I believe that, taken together, much of the evidence gathered to date suggests that close-range transmission by aerosols is significant — possibly very significant, and certainly more significant than direct droplet spray.

But basic physics also says that a 5-micron droplet takes about a half-hour to drop to the floor from the mouth of an adult of average height — and during that time, the droplet can travel many meters on an air current. Droplets expelled in coughs or sneezes also travel much farther than one meter.

Wear a mask. Masks help block aerosols released by the wearer. Scientific evidence is also building that masks protect the wearer from breathing in aerosols around them.

When it comes to masks, size does matter.

My lab has been testing cloth masks on a mannequin, sucking in air through its mouth at a realistic rate. We found that even a bandanna loosely tied over its mouth and nose blocked half or more of aerosols larger than 2 microns from entering the mannequin.

Ventilation counts. Open windows and doors. Adjust dampers in air-conditioning and heating systems. Upgrade the filters in those systems. Add portable air cleaners, or install germicidal ultraviolet technologies to remove or kill virus particles in the air.

Avoid crowds. The more people around you, the more likely someone among them will be infected. Especially avoid crowds indoors, where aerosols can accumulate.

We also found that especially with very small aerosols — smaller than 1 micron — it is more effective to use a softer fabric (which is easier to fit tightly over the face) than a stiffer fabric (which, even if it is a better filter, tends to sit more awkwardly, creating gaps).

One study from 2013 found that surgical masks reduced exposure to flu viruses by between 10 percent and 98 percent (depending on the mask’s design).A recent paper found that surgical masks can completely block seasonal coronaviruses from getting into the air.To my knowledge, no similar study has been conducted for SARS-CoV-2 yet, but these findings might apply to this virus as well since it is similar to seasonal coronaviruses in size and structure.

What about the outbreak on the Diamond Princess cruise ship off Japan early this year? Some 712 of the 3,711 people on board became infected.

Consider the case of a restaurant in Guangzhou, southern China, at the beginning of the year, in which one diner infected with SARS-CoV-2 at one table spread the virus to a total of nine people seated at their table and two other tables.Yuguo Li, a professor of engineering at the University of Hong Kong, and colleagues analyzed video footage from the restaurant and in a preprint (not peer reviewed) published in April found no evidence of close contact between the diners.Droplets can’t account for transmission in this case, at least not among the people at the tables other than the infected person’s: The droplets would have fallen to the floor before reaching those tables.But the three tables were in a poorly ventilated section of the restaurant, and an air conditioning unit pushed air across them. Notably, too, no staff member and none of the other diners in the restaurant — including at two tables just beyond the air conditioner’s airstream — became infected.

The average daily death toll in the United States is inching back toward 1,000, and hospitals nationwide are strained with patients. The president-elect said that Americans would need to rely on basic precautions, like wearing masks, to “get back to normal as fast as possibl

The country now averages 900 deaths each day, and 28 states added more cases in the seven-day period ending Sunday than in any other weeklong stretch of the pandemic. No states are reporting sustained reductions in cases.

Coronavirus hospitalizations, perhaps the clearest measure of how many people are severely ill, are approaching record levels set during earlier surges of the pandemic, according to data collected by the Covid Tracking Project

At the White House, which has been the site of several high-profile outbreaks in recent months, Ben Carson, the secretary of housing and urban development, tested positive for the coronavirus on Monday, according to a spokesman for the agency. He became the latest in a long list of administration officials, including Mr. Trump himself, to contract the virus.

At least three people who attended an election party at the White House last week, including Mr. Carson, have tested positive for the virus. At the event, several hundred people gathered in the East Room for several hours, many of them not wearing masks as they mingled while watching the election returns.

Beyond the impact of the virus itself, when Mr. Biden takes office, he will face a sobering economic reality.

There were 10 million fewer Americans working in October than in February, according to the Labor Department, and the pace of job growth has slowed every month since June.

Mr. Biden, moving to signal to Americans that he is prepared to take charge after a chaotic year, named a new coronavirus task force headed by a former commissioner of food and drugs, Dr. David Kessler; a former surgeon general, Dr. Vivek Murthy; and a Yale public health expert, Dr. Marcella Nunez-Smith.

The president-elect vowed to “spare no effort” in fighting the virus, with the goal of getting the economy “running at full speed again.”

His comments contrasted Mr. Trump’s. The president has spent the past eight months dismissing or playing down the need for Americans to wear masks, saying frequently — and falsely — that public health experts disagree about masks’ effectiveness.

Vice President Mike Pence, who serves as the chairman of Mr. Trump’s coronavirus task force, convened the group on Monday after meeting about once a week over the past several months. But Mr. Trump, who remains in office until January, is openly at odds with his own virus advisers, including about mask wearing.

More than half of the states issued mask mandates at some point this year, and some officials have tried targeted shutdowns on bars and indoor dining. But public health officials acknowledge that there is little public appetite for a return to full lockdowns.

“The virus is winning the war by now,” Mr. Pritzker said, urging the public to wear masks. “The situation has worsened considerably in certain areas of the state.”

In New York City, Mayor Bill de Blasio warned on Monday that the city was “getting dangerously close” to a second wave and said that further lockdowns were possible if New Yorkers did not regain control of the virus. “Unfortunately, it could mean even having to shut down parts of our economy again,” he said.At Mr. Biden’s closed-door briefing with his Covid advisory board, which took place remotely over a video conference call on Monday, three leaders of the panel provided updates on the pandemic while others members of the group introduced themselves, according to a person familiar with the discussion.

He told lawmakers that officials in the government had failed to heed his warnings about acquiring masks and other supplies