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The COVID-19 epidemic altered life as we know it and may have also altered each of us personally, altering everything from our daily rituals to our life objectives and ambitions.

Although every person's circumstance is unique, many people have realized that it is possible to remain resilient amid a crisis.

Many of us have realized how dependent we are on others, and many have been able to preserve their social relationships while having to utilize technology to stay in touch.

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The COVID-19 pandemic changed life as we know it-and it may have changed us individually as well, from our morning routines to our life goals and priorities. Many say the world has changed forever. But this coming year, if the vaccines drive down infections and variants are kept at bay, life could return to some form of normal. At that point, what will we glean from the past year? Are there silver linings or lessons learned?

"Humanity's memory is short, and what is not ever-present fades quickly," says Manisha Juthani, MD, a Yale Medicine infectious diseases specialist. The bubonic plague, for example, ravaged Europe in the Middle Ages-resurfacing again and again-but once it was under control, people started to forget about it, she says. "So, I would say one major lesson from a public health or infectious disease perspective is that it's important to remember and recognize our history. This is a period we must remember."

We asked our Yale Medicine experts to weigh in on what they think are lessons worth remembering, including those that might help us survive a future virus or nurture a resilience that could help with life in general.

Lesson 1: Masks are useful tools

What happened: The Centers for Disease Control and Prevention (CDC) recently relaxed its masking guidance for those who have been fully vaccinated. But when the pandemic began, it necessitated a global effort to ensure that everyone practiced behaviors to keep themselves healthy and safe-and keep others healthy as well. This included the widespread wearing of masks indoors and outside.

What we've learned: Not everyone practiced preventive measures such as mask wearing, maintaining a 6-foot distance, and washing hands frequently. But, Dr. Juthani says, "I do think many people have learned a whole lot about respiratory pathogens and viruses, and how they spread from one person to another, and that sort of old-school common sense-you know, if you don't feel well-whether it's COVID-19 or not-you don't go to the party. You stay home."

Masks are a case in point. They are a key COVID-19 prevention strategy because they provide a barrier that can keep respiratory droplets from spreading. Mask-wearing became more common across East Asia after the 2003 SARS outbreak in that part of the world. "There are many East Asian cultures where the practice is still that if you have a cold or a runny nose, you put on a mask," Dr. Juthani says.

She hopes attitudes in the U.S. will shift in that direction after COVID-19. "I have heard from a number of people who are amazed that we've had no flu this year-and they know masks are one of the reasons," she says. "They've told me, 'When the winter comes around, if I'm going out to the grocery store, I may just put on a mask.'"

Lesson 2: Telehealth might become the new normal

What happened: Doctors and patients who have used telehealth (technology that allows them to conduct medical care remotely), found it can work well for certain appointments, ranging from cardiology check-ups to therapy for a mental health condition. Many patients who needed a medical test have also discovered it may be possible to substitute a home version.

What we've learned: While there are still problems for which you need to see a doctor in person, the pandemic introduced a new urgency to what had been a gradual switchover to platforms like Zoom for remote patient visits.

More doctors also encouraged patients to track their blood pressure at home, and to use at-home equipment for such purposes as diagnosing sleep apnea and even testing for colon cancer. Doctors also can fine-tune cochlear implants remotely.

"It happened very quickly," says Sharon Stoll, DO, a neurologist. One group that has benefitted is patients who live far away, sometimes in other parts of the country-or even the world, she says. "I always like to see my patients at least twice a year. Now, we can see each other in person once a year, and if issues come up, we can schedule a telehealth visit in-between," Dr. Stoll says. "This way I may hear about an issue before it becomes a problem, because my patients have easier access to me, and I have easier access to them."

Meanwhile, insurers are becoming more likely to cover telehealth, Dr. Stoll adds. "That is a silver lining that will hopefully continue."

Lesson 3: Vaccines are powerful tools

What happened: Given the recent positive results from vaccine trials, once again vaccines are proving to be powerful for preventing disease.

What we've learned: Vaccines really are worth getting, says Dr. Stoll, who had COVID-19 and experienced lingering symptoms, including chronic headaches. "I have lots of conversations-and sometimes arguments-with people about vaccines," she says. Some don't like the idea of side effects. "I had vaccine side effects and I've had COVID-19 side effects, and I say nothing compares to the actual illness. Unfortunately, I speak from experience."

Dr. Juthani hopes the COVID-19 vaccine spotlight will motivate people to keep up with all of their vaccines, including childhood and adult vaccines for such diseases as measles, chicken pox, shingles, and other viruses. She says people have told her they got the flu vaccine this year after skipping it in previous years. (The CDC has reported distributing an exceptionally high number of doses this past season.)

But, she cautions that a vaccine is not a magic bullet-and points out that scientists can't always produce one that works. "As advanced as science is, there have been multiple failed efforts to develop a vaccine against the HIV virus," she says. "This time, we were lucky that we were able build on the strengths that we've learned from many other vaccine development strategies to develop multiple vaccines for COVID-19."

Lesson 4: Everyone is not treated equally, especially in a pandemic

What happened: COVID-19 magnified disparities that have long been an issue for a variety of people.

What we've learned: Racial and ethnic minority groups especially have had disproportionately higher rates of hospitalization for COVID-19 than non-Hispanic white people in every age group, and many other groups faced higher levels of risk or stress. These groups ranged from working mothers who also have primary responsibility for children, to people who have essential jobs, to those who live in rural areas where there is less access to health care.

"One thing that has been recognized is that when people were told to work from home, you needed to have a job that you could do in your house on a computer," says Dr. Juthani. "Many people who were well off were able do that, but they still needed to have food, which requires grocery store workers and truck drivers. Nursing home residents still needed certified nursing assistants coming to work every day to care for them and to bathe them."

As far as racial inequities, Dr. Juthani cites President Biden's appointment of Yale Medicine's Marcella Nunez-Smith, MD, MHS, as inaugural chair of a federal COVID-19 Health Equity Task Force. "Hopefully the new focus is a first step," Dr. Juthani says.

Lesson 5: We need to take mental health seriously

What happened: There was a rise in reported mental health problems that have been described as "a second pandemic," highlighting mental health as an issue that needs to be addressed.

What we've learned: Arman Fesharaki-Zadeh, MD, PhD, a behavioral neurologist and neuropsychiatrist, believes the number of mental health disorders that were on the rise before the pandemic is surging as people grapple with such matters as juggling work and childcare, job loss, isolation, and losing a loved one to COVID-19.

The CDC reports that the percentage of adults who reported symptoms of anxiety of depression in the past 7 days increased from 36.4 to 41.5 % from August 2020 to February 2021. Other reports show that having COVID-19 may contribute, too, with its lingering or long COVID symptoms, which can include "foggy mind," anxiety, depression, and post-traumatic stress disorder.

"We're seeing these problems in our clinical setting very, very often," Dr. Fesharaki-Zadeh says. "By virtue of necessity, we can no longer ignore this. We're seeing these folks, and we have to take them seriously."

Lesson 6: We have the capacity for resilience

What happened: While everyone's situation is different (and some people have experienced tremendous difficulties), many have seen that it's possible to be resilient in a crisis.

What we've learned: People have practiced self-care in a multitude of ways during the pandemic as they were forced to adjust to new work schedules, change their gym routines, and cut back on socializing. Many started seeking out new strategies to counter the stress.

"I absolutely believe in the concept of resilience, because we have this effective reservoir inherent in all of us-be it the product of evolution, or our ancestors going through catastrophes, including wars, famines, and plagues," Dr. Fesharaki-Zadeh says. "I think inherently, we have the means to deal with crisis. The fact that you and I are speaking right now is the result of our ancestors surviving hardship. I think resilience is part of our psyche. It's part of our DNA, essentially."

Dr. Fesharaki-Zadeh believes that even small changes are highly effective tools for creating resilience. The changes he suggests may sound like the same old advice: exercise more, eat healthy food, cut back on alcohol, start a meditation practice, keep up with friends and family. "But this is evidence-based advice-there has been research behind every one of these measures," he says.

But we have to also be practical, he notes. "If you feel overwhelmed by doing too many things, you can set a modest goal with one new habit-it could be getting organized around your sleep. Once you've succeeded, move on to another one. Then you're building momentum."

Lesson 7: Community is essential-and technology is too

What happened: People who were part of a community during the pandemic realized the importance of human connection, and those who didn't have that kind of support realized they need it.

What we've learned: Many of us have become aware of how much we need other people-many have managed to maintain their social connections, even if they had to use technology to keep in touch, Dr. Juthani says. "There's no doubt that it's not enough, but even that type of community has helped people."

Even people who aren't necessarily friends or family are important. Dr. Juthani recalled how she encouraged her mail carrier to sign up for the vaccine, soon learning that the woman's mother and husband hadn't gotten it either. "They are all vaccinated now," Dr. Juthani says. "So, even by word of mouth, community is a way to make things happen."

It's important to note that some people are naturally introverted and may have enjoyed having more solitude when they were forced to stay at home-and they should feel comfortable with that, Dr. Fesharaki-Zadeh says. "I think one has to keep temperamental tendencies like this in mind."

But loneliness has been found to suppress the immune system and be a precursor to some diseases, he adds. "Even for introverted folks, the smallest circle is preferable to no circle at all," he says.

Lesson 8: Sometimes you need a dose of humility

What happened: Scientists and nonscientists alike learned that a virus can be more powerful than they are. This was evident in the way knowledge about the virus changed over time in the past year as scientific investigation of it evolved.

What we've learned: "As infectious disease doctors, we were resident experts at the beginning of the pandemic because we understand pathogens in general, and based on what we've seen in the past, we might say there are certain things that are likely to be true," Dr. Juthani says. "But we've seen that we have to take these pathogens seriously. We know that COVID-19 is not the flu. All these strokes and clots, and the loss of smell and taste that have gone on for months are things that we could have never known or predicted. So, you have to have respect for the unknown and respect science, but also try to give scientists the benefit of the doubt," she says.

"We have been doing the best we can with the knowledge we have, in the time that we have it," Dr. Juthani says. "I think most of us have had to have the humility to sometimes say, 'I don't know. We're learning as we go.'"

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8 Lessons We Can Learn From the COVID-19 Pandemic

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The COVID-19 pandemic changed life as we know it. As people start to think about what returning to normal will look like, some are asking the question: What have we learned from this? Yale Medicine doctors share their thoughts.

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When the coronavirus pandemic arrived, the majority of those employed in the music industry were impacted .

While they wait for government support, music venues lie idle, racking up debt, and in danger of closing permanently.

David Mayeri, the CEO of Berkeley's nonprofit UC Theatre and a leader in the National Independent Venue Association (NIVA), a national group that was formed in reaction to the epidemic, adds, "We've got rent to pay, we've got mortgages to pay.

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Princess Nokia performs at the 2019 Noise Pop Music and Arts Festival. (Estefany Gonzalez )

Update, Dec. 21: The Save Our Stages Act has been included in the COVID-19 stimulus package. Read more.

Fast forward to the coronavirus pandemic, and most of those jobs are gone. Music venues sit empty, accruing debt and on the brink of permanent closure, as they await government assistance.

Despite their importance to culture and the economy alike, venues have been all but forgotten in the United States' woefully inadequate COVID-19 recovery plan. On the federal level, the Save Our Stages Act, which would provide substantial grant funding to independent venues, has remained stuck in limbo as the Republican-controlled Senate continues to delay a second stimulus package, leaving millions of Americans hungry and facing eviction.

Indeed, The Stud, San Francisco's oldest LGBTQ+ venue, shuttered in May. And Oakland has lost eclectic concert hall Starline Social Club, punk dive Stork Club, Afro-futurist warehouse venue Spirithaus and The Uptown Nightclub.

"We have an emergency reserve. It's possible we could pull some money from that," he says. "I think this is incredibly urgent, and if there's any flexibility with spending, this should be something that is prioritized-even as a lifeline for the next three months to get us to a point where, hopefully, we have more robust support from federal government."

That won't happen until the vaccine is widely available-which means that venues will continue to bleed money, and go out of business, until the federal stimulus arrives.

Federal government help is also crucial in order for California to step in on a state level, says State Senator Scott Wiener. "Only Congress has the ability to deficit spend, only the federal government has the ability to print money. We need a significant new PPP program to support these businesses," he says.

Wiener says Governor Gavin Newsom has expressed an urgency to help small businesses in the next budget cycle in January. Indeed, Newsom recently announced a new, $500 million program that will distribute grants of up to $25,000 to small businesses. But given venues' huge monthly costs-and the fact that financial analysts predict that California could be operating at a deficit through 2024 -federal funds will still be needed to make a major difference for music venues.

"We have to balance our budget so we have far more constraints, but I don't think the state has done enough to financially support small businesses, and particularly those that simply cannot reopen," Wiener continues. "I know that will be a focus as we go back and go into the budget process."

California's commercial eviction moratorium helps, but it also leaves music venues on the hook for back-rent after March 2021. It's highly improbable that they'll resume business by then. (The State Legislature killed a bill sponsored by Wiener that would have extended eviction protections through the end of the pandemic-it was strongly opposed by the real estate industry.)

Once a music venue gets evicted or breaks its lease, it may be gone forever. That's because of a lack of adequate rental properties, argues Allen Scott, a co-owner of The Independent and The New Parish and the head of concerts and festivals at Another Planet Entertainment. "If you're the owner of a restaurant, you lay off all your employees, you break your lease, you cancel your insurance-you literally get rid of every expense that you have. Your hope is that when you can open back up again, you can negotiate a new lease ... and you can move forward," Scott says. "A music venue cannot do that because there are not that many spaces we can go into-otherwise it would be a lot easier of a business."

Other Options While the Federal Stimulus Stalls?

Even as city and state governments await federal funding, some entertainment industry leaders say there's more that can be done locally to support live music.

One criticism has come from arts presenters who feel that the performing arts have been unfairly left out of California's reopening efforts. Before the current upswing of COVID-19 cases that landed most of California in the purple tier, indicating unmitigated spread, San Francisco moved to allow indoor dining at 25% capacity of up to 100 people; outdoor religious services with up to 200 people were also allowed. But there was no official pathway for outdoor, masked and socially distanced performing arts events-even though the city didn't stop thousands of people from partying on Ocean Beach during Burning Man weekend.

The lack of consistency frustrated venue owners and arts presenters, who believe that they have the tools and expertise to throw safe gatherings-and badly need the income. "We have hundreds of people who work for us who we'd like to give some employment to, some artists we'd like to give employment to ... and more than anything else, create an environment that would be safer than what is currently happening," Fred Barnes, general manager of The Chapel and co-founder of the Independent Venue Alliance, said at an August Entertainment Commission hearing.

Even after releasing the JAM Permit for music in outdoor dining and other public areas, the city attempted to shut down a 49-person-capacity outdoor performance from the San Francisco International Arts Festival (SFIAF). In an email to KQED, a spokesperson from the City Attorney's office called it a potential "super spreader event." In October, the SFIAF filed a lawsuit against the city of San Francisco and state of California, claiming that the performing arts should be the same way as religious services and political activity in California and San Francisco's reopening efforts because they, too, are protected by the first amendment.

"We just want parity with those types of activities," says SFIAF director Andrew Wood. The governor's office sided with SFIAF in court and issued an interim directive to allow outdoor performances with 100 attendees or fewer pending local health officials' approval. But the city of San Francisco is still in a legal battle with SFIAF, and the festival is using its virtual holiday party to raise money for legal fees.

Social gatherings of any kind are off while California remains in the purple tier. But Wood says he wants the court to recognize the arts as a first amendment-protected activity so that they can be included in future reopening plans when virus rates go down and other activities like outdoor dining resume.

Shannon Amitin from the Queer Nightlife Fund agrees. The nonprofit organization has been giving out micro-grants to bartenders, sound techs, performers and DJs from LGBTQ+ bars and clubs since the pandemic started. Amitin says that in addition to improving the unemployment system, which has subjected some furloughed workers to months-long wait times for relief, the city can help independent promoters and artists by providing guidelines for outdoor, socially distanced events that aren't tethered to outdoor dining. "We really need to take a harm reduction approach to events," says Amitin. "Folks are still going to gather, so let's give them the tools and the ability to do it safely."

For the San Francisco Venue Coalition's part, Lowdermilk says that it only makes financial sense for its venues to operate at 100% capacity. "We don't want to push this. We want our patrons and staff to be healthy," he says. "And we're only interested in reopening at full capacity. Any sort of limited-capacity situation doesn't make sense for us-the numbers don't work out for venues. ... It's a very low-margin industry as it is, and we need to fill our rooms to be profitable."

"We're anchor tenants to neighborhoods, economic drivers and employers," says Casey Lowdermilk, the assistant general manager of Bill Graham Civic Auditorium and an organizer with the San Francisco Venue Coalition and NIVA. "Losing venues will have devastating impacts for our community-not only economically, but culturally."

A Lifeline for Venues?

Even if the intrinsic value of art doesn't move politicians to act, the live music industry's financial impact has been a persuasive tool for organizers. By coming together across the United States, the venue owners of NIVA have flexed their collective economic muscle. "We are now seen as a very viable, organized group," says Mayeri.

"Both sides, Democrats and Republicans, believe that saving arts and culture across the country, saving our stages, is important in the fabric of communities," he continues, referencing a Chicago study that found that every dollar spent on live entertainment generates $12 for the local economy.

Thanks to NIVA's awareness campaign in Congress, Mayeri is optimistic that the Save Our Stages Act now has support on both sides of the aisle, and it is included in the Senate's bipartisan relief bill. But Senate Republicans and Democrats have continued to clash over and further delay the stimulus package, with the legislative session soon coming to an end.

Federal relief is crucial to save venues, but Mayeri also believes California can do more. Even before the pandemic, independent music venues already operated on razor-thin profit margins because of high real estate costs. "The state of California should have a $50- to $100-million fund to support music venues and performing arts theaters," Mayeri proposes. As of the 2019 fiscal year, California ranks 26th compared to other U.S. states in per capita spending on the arts.

"We have to rebuild-we've been decimated," says longtime artist manager Michelle Campbell, whose clients, like rapper Mahawam, have built up their fan bases by touring independent venues. "We need funding for that, [even] if you have to entice corporations, give them tax write-offs and have them donate to cultural endowment funds. ... There needs be something on all levels-city, state and federal-to rebuild the cultural landscape, because it's going to be different. Especially when you have these long-term bars and venues that have closed permanently, like Starline, which was our cultural hub. How do we get something like that back? You have to be intentional."

On the city level, the city of Berkeley, where the UC Theatre is located, had one of the swiftest pandemic responses of any Bay Area municipalities when it comes to the arts. In April, the city began distributing $4.5 million in relief funding among arts nonprofits, small businesses and vulnerable tenants. San Francisco and Oakland have led their own relief effort that have included grants and loans for small businesses, arts nonprofits and individual artists. Additionally, San Francisco has waived payroll taxes and other government expenses for bars and clubs, and created the JAM Permit, which made it easier to book live music in outdoor dining areas and other city-designated Shared Spaces before the region went into its current lockdown.

But as the San Francisco Venue Coalition argues, these efforts, while appreciated, have been insufficient to address the specific needs of music venues. Payroll taxes, for instance, are only a small fraction of a venue's expenditures, and the JAM Permit is geared towards a restaurant booking a jazz trio or DJ, not a promoter putting on an outdoor concert. The SFVC wants direct financial support instead.

Lowdermilk and the SFVC have given the San Francisco Entertainment Commission a detailed policy proposal that asks for $48 million in funding for independent venues. This would allow the city to cover the operating costs of around 50 venues for 16-18 months of closure with the funds it receives from the federal government's second stimulus package.

"That will be a one-time payment, and hopefully by next summer we'll reopen, and hopefully venues will have survived," Lowdermilk says. "I think there are a lot of opportunities for our city government to help us, and we want to be there to be able to have that economic activity on the return, to help our city recover."

Without Federal Help, California's Options are Limited

The SFVC's proposal is currently being considered by the Entertainment Commission, but it would require the approval of Mayor London Breed, whose office told KQED in a statement that without federal funding, the city is stretched beyond its capacity to maintain even its basic services. Acknowledging the hardships small businesses face, a spokesperson for the mayor wrote that the city's CARES Act funding from the first stimulus package has been spent on the immediate needs of the pandemic, such as testing, quarantine housing, contact tracing, food security and personal protective equipment.

"Without additional financial support from the federal government, cities all across the country, like San Francisco, will need to make budget cuts and hard trade-offs," the mayor's office wrote, adding that even basic services, such as the Municipal Transportation Agency, are facing potential layoffs and budget cuts. "San Francisco needs additional federal support in the weeks and months ahead so that we can continue our COVID-19 response [and] support businesses-including entertainment and nightlife venues-and stabilize city services like Muni."

San Francisco Supervisor Matt Haney, who represents the nightlife-heavy Tenderloin and South of Market neighborhoods, says that his office is exploring other funding opportunities for venues, even if federal relief doesn't come in the near future.

At the state level, the COVID-19 crisis has plunged California into a deficit; the state has had to tap into its rainy day fund to avoid major cuts to essentials like K-12 education, and state lawmakers say relief for live music is unlikely without more federal funds. And on the city level, San Francisco, Oakland and Berkeley have given various pandemic-relief grants to artists, arts nonprofits and small businesses. But most of these grants have been doled out in one-time payments of $25,000 or less, which hasn't come close to covering music venues' costs. The San Francisco Venue Coalition estimates that the average monthly overhead of a typical San Francisco club is $18,000-$35,000.

A vaccine on the horizon offers a glimmer of hope that the concert business may resume in the second half of 2021. Until then, "We've got rent to pay, we've got mortgages to pay," says David Mayeri, the CEO of Berkeley's nonprofit UC Theatre and an organizer with the National Independent Venue Association (NIVA), a nationwide coalition that sprang up in response to the pandemic. NIVA has over 100 members in Northern California. "The financial burden is just enormous, and a lot of clubs are going out of business," he says.
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Ask anyone who misses the catharsis of a good, sweaty dance party or mosh pit-so much magic can happen within the four walls of a concert hall.

In the 1960s, San Francisco's Fillmore was where the Grateful Dead and Sly and the Family Stone honed their psychedelic sound. In the late '80s and early '90s, MC Hammer brought Oakland party rap to the world with a music video filmed at Sweet Jimmie's, and Green Day made a name for themselves at Berkeley's all-ages punk spot 924 Gilman. More recently, Slim's in San Francisco was the springboard for platinum-selling rapper G-Eazy's first headlining tour.

Over the decades, the Bay Area's music venues have been where people go to forge connections, build communities and experience new forms of creativity. Additionally, venues have had an outsized impact on the local economy by drawing music fans to neighborhoods where they spend money on pre-show drinks, late-night tacos, transportation and hotels. According to the most recent study from the San Francisco Controller's Office, nightlife generated $6 billion for the local economy in 2015 and created 60,000 jobs.

Despite their importance to culture and the economy alike, venues have been all but forgotten in the United States' woefully inadequate COVID-19 recovery plan.

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2020 Decimated the Concert Industry-And It Can't Rebuild Without Government Help | KQED

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Princess Nokia performs at the 2019 Noise Pop Music and Arts Festival. (Estefany Gonzalez ) Update, Dec. 21: The Save Our Stages Act has been included in the COVID-19 stimulus package. Read more. Fast forward to the coronavirus pandemic, and most of those jobs are gone.

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A significant economic shock has been brought on by coronavirus disease 2019 (COVID-19), in addition to its effects on public health.

A study showed how vulnerable many small business firms' finances are.

Employees were impacted.

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Masks prevent the spread of the virus

Studies show that cloth mask materials may filter out tiny droplets and particles smaller than 10 microns, hence reducing users' exposure to infectious droplets.

The main way that the SARS-CoV-2 illness is spread is by the inhalation of respiratory droplets that are produced when people cough, sneeze, sing, talk, or breathe.

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Centers for Disease Control and Prevention

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Important update: Healthcare facilities

CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more

Science Brief: Community Use of Masks to Control the Spread of SARS-CoV-2

COVID-19 Science Briefs provide a summary of the scientific evidence used to inform specific CDC guidance and recommendations. The Science Briefs reflect the scientific evidence, and CDC's understanding of it, on a specific topic at the time of the Brief's publication. Though CDC seeks to update Science Briefs when and as appropriate, given ongoing changes in scientific evidence an individual Science Brief might not reflect CDC's current understanding of that topic. As scientific evidence and available information on COVID-19 change, Science Briefs will be systematically archived as historic reference materials.

Page First Published Nov 10, 2020 | View Page Updates

Background

SARS-CoV-2 infection is transmitted predominantly by inhalation of respiratory droplets generated when people cough, sneeze, sing, talk, or breathe. CDC recommends community use of masks to prevent transmission of SARS-CoV-2. Masks are primarily intended to reduce the emission of virus-laden droplets by the wearer ("source control"), which is especially relevant for asymptomatic or presymptomatic infected wearers who feel well and may be unaware of their infectiousness to others (estimated to account for more than 50% of SARS-CoV-2 transmissions). 1, 2 Masks also help reduce inhalation of these droplets by the wearer ("filtration for wearer protection"). The community benefit of masking for SARS-CoV-2 control is due to the combination of these two effects (source control and filtration for wearer protection); individual prevention benefit increases with increasing numbers of people using masks consistently and correctly.

Source Control to Block Exhaled Virus

Multi-layer cloth masks block release of exhaled respiratory particles into the environment, ³⁻⁶ along with any microorganisms associated with these particles. 7, 8 Cloth masks not only effectively block most large droplets (i.e., 20-30 microns and larger), ⁹ but they can also block the exhalation of fine droplets and particles (also often referred to as aerosols) smaller than 10 microns 3, 5 which increase in number with the volume of speech ¹⁰⁻¹² and specific types of phonation. ¹³ Multi-layer cloth masks can both block 50-70% of these fine droplets and particles 3, 14 and limit the forward spread of those that are not captured. 5, 6, 15, 16 Upwards of 80% blockage has been achieved in human experiments, ⁴ with cloth masks in some studies performing on par with surgical masks as barriers for source control. 3, 9, 14, 17 In one study, conducted prior to widespread circulation of the Delta variant, masks worked equally well for blocking aerosolized particles containing both "wild-type" virus and the Alpha variant (a more infectious variant). ¹⁷

Filtration for Wearer Protection

Studies demonstrate that cloth mask materials can also reduce wearers' exposure to infectious droplets through filtration, including filtration of fine droplets and particles less than 10 microns. The relative filtration effectiveness of various masks has varied widely across studies, in large part due to variation in experimental design and particle sizes analyzed. Multiple layers of cloth with higher thread counts have demonstrated superior performance compared to single layers of cloth with lower thread counts, in some cases filtering nearly 50% of fine particles less than 1 micron. 14, 18-30 Some materials (e.g., polypropylene) may enhance filtering effectiveness by generating triboelectric charge (a form of static electricity) that enhances capture of charged particles 20 while others (e.g., silk) may help repel moist droplets ³¹ and reduce fabric wetting and thus maintain breathability and comfort. In addition to the number of layers and choice of materials, other techniques can improve wearer protection by improving fit and thereby filtration capacity. Examples include but are not limited to mask fitters, knotting-and-tucking the ear loops of medical procedures masks, using a cloth mask placed over a medical procedure mask, and nylon hosiery sleeves. ³²⁻³⁶

Human Studies of Masking and SARS-CoV-2 Transmission

A large, well-designed cluster-randomized trial in Bangladesh in late 2020 found that surgical or cloth mask distribution, role-modeling, and active mask promotion tripled mask use to 42.3% in intervention villages compared to 13.3% in comparison villages. In villages receiving mask interventions, symptomatic seroprevalence of SARS-CoV-2 was reduced by approximately 9% relative to comparison villages. In villages randomized to receive surgical masks, symptomatic seroprevalence of SARS-CoV-2 was significantly lower (relative reduction 11.1% overall). The results of this study show that even modest increases in community use of masks can effectively reduce symptomatic SARS-CoV-2 infections (COVID-19).³⁷

A study of an outbreak aboard the USS Theodore Roosevelt, an environment notable for congregate living quarters and close working environments, found that use of face coverings on-board was associated with a 70% reduced risk of infection.³⁸

In a study of 124 Beijing households with > 1 laboratory-confirmed case of SARS-CoV-2 infection, mask use by the index patient and family contacts before the index patient developed symptoms reduced secondary transmission within the households by 79%.³⁹

A study examining SARS-CoV-2 secondary attack rates among eight public K-12 school districts in Massachusetts (70 schools with >33,000 enrolled students) during the 2020-21 school year found an unadjusted secondary attack rate of 11.7% for unmasked versus 1.7% for masked interactions.⁴⁰

A retrospective case-control study from Thailand documented that, among more than 1,000 persons interviewed as part of contact tracing investigations, those who reported having always worn a mask during high-risk exposures experienced a greater than 70% reduced risk of acquiring infection compared with persons who did not wear masks under these circumstances.⁴¹

During July 15-August 31, 2021, when Delta was the predominant strain circulating in the U.S., about one in five K-12 public non-charter schools open for in-person learning in Maricopa and Pima Counties, Arizona, experienced a school-associated outbreak. Outbreaks were three and a half times more likely (adjusted odds ratio 3.5, 95% confidence interval 1.8-6.6) in schools without mask mandates.⁴²

In a nationwide analysis of data collected during July 1-September 4, 2021, U.S. counties without school mask requirements experienced larger increases in pediatric COVID-19 case rates (18.53 per 100,000 per day more cases) after the start of school compared with counties with school mask requirements.⁴³

An investigation of a high-exposure event in the U.S., in which 2 symptomatically ill hair stylists interacted for an average of 15 minutes with each of 139 clients during an 8-day period, found that none of the 67 clients who subsequently consented to an interview and testing developed infection. The stylists and all clients universally wore masks in the salon as required by local ordinance and company policy at the time.⁴⁴

Investigations involving infected passengers aboard flights longer than 10 hours strongly suggest that masking prevented in-flight transmissions, as demonstrated by the absence of infection developing in other passengers and crew in the 14 days following exposure.45, 46

At least ten studies have confirmed the benefit of universal masking in community level analyses: in a unified hospital system, ⁴⁷ a German city, ⁴⁸ two U.S. states, 49, 50 a panel of 15 U.S. states and Washington, D.C., 51, 52 as well as both Canada ⁵³ and the U.S. ⁵⁴⁻⁵⁶ nationally. Each analysis demonstrated that, following directives from organizational and political leadership for universal masking, new infections fell significantly. Two of these studies 51, 52 and an additional analysis of data from 200 countries that included the U.S. ⁵⁶ also demonstrated reductions in mortality. Another 10-site study showed reductions in hospitalization growth rates following mask mandate implementation. ⁵⁴ A separate series of cross-sectional surveys in the U.S. suggested that a 10% increase in self-reported mask wearing tripled the likelihood of stopping community transmission. ⁵⁷ An economic analysis using U.S. data found that, given these effects, increasing universal masking by 15% could prevent the need for lockdowns and reduce associated losses of up to $1 trillion or about 5% of gross domestic product. ⁵²

Two studies have been improperly characterized by some sources as showing that surgical or cloth masks offer no benefit. 58,59 A community-based randomized control trial in Denmark during 2020 assessed whether the use of surgical masks reduced the SARS-CoV-2 infection rate among wearers (personal protection) by more than 50%. ⁵⁸ Findings were inconclusive, ⁵⁸ most likely because the actual reduction in infections was lower. The study was too small (i.e., enrolled about 0.1% of the population) to assess whether masks could decrease transmission from wearers to others (source control). A second study of 14 hospitals in Vietnam during 2015 found that cloth masks were inferior to surgical masks for protection against clinical upper respiratory illness or laboratory-confirmed viral infection. ⁵⁹ The study had a number of limitations including the lack of a true control (no mask) group for comparison, limited source control as hospitalized patients and staff were not masked, unblinded study arm assignments potentially biasing self-reporting of illness, and the washing and re-use of cloth masks by users introducing the risk of infection from self-washing. A follow up study in 2020 found that healthcare workers whose cloth masks were laundered by the hospital were protected equally as well as those that wore medical masks. ⁶⁰

Potential Adverse Health Effects of Mask Wearing
Adults
Research supports that under most circumstances, mask wearing has no significant adverse health effects for wearers. Studies of healthy hospital workers, older adults, and adults with chronic obstructive pulmonary disease (COPD) reported no to minimal changes in oxygen or carbon dioxide levels while wearing a cloth or surgical mask either during rest or moderate physical activity. ⁶¹⁻⁶⁵ The safety of mask use during low to moderate levels of exercise has been confirmed in studies of healthy adults and adolescents. 64, 66-70 Some, ⁷¹⁻⁷⁴ but not all, ⁶⁷ studies have found that during intense exercise, especially when approaching the aerobic threshold, wearing a mask can increase dyspnea (difficulty breathing), perceived exertion, and claustrophobia, and produce modest negative effects on measured cardiopulmonary parameters. In some people, face masks worn for longer durations might be associated with skin reactions such as acne, itching, dry skin and worsening of existing dermatoses. ⁷⁵⁻⁷⁷ Wearing a surgical mask and N95 respirator may have a higher risk of skin reactions compared with a cloth mask. ⁷⁶⁻⁷⁸
Children
A study of 60 elementary school children reported no adverse cardiovascular (e.g., heart rate) or pulmonary (e.g., peripheral oxygen saturation) effects among children while wearing a cloth face covering in a classroom for 30 consecutive minutes of instructional time. ⁷⁹ A separate study observed no oxygen desaturation or respiratory distress after 60 minutes of monitoring among children less than 2 years of age when masked during normal play. ⁸⁰ A randomized trial among 40 children aged 3-10 years old scheduled for elective surgery, found that protective surgical face masks could be used safely in the postoperative period. ⁸¹ In a prospective school-based cohort study of children aged 10-17 years who wore masks for 6-7 hours during the school day, some children self-reported general (4-7%) or situation-specific (2-4%) side-effects such as skin irritation, headache, or difficulty breathing during physical education. ⁸²

The potential impact of masks on language and emotional development has been examined in several studies. ⁸³⁻⁸⁹ Some research suggests children and adults, and especially toddlers (aged 3-5 years) can have difficulty inferring emotion from facial features presented on photographs of persons with their lower facial features covered by a mask. ⁸³ However, a study of 7- to 13-year-old children determined the decrement in emotional inference observed when the lower half of a photographed face was covered with a mask was equivalent to that associated with covering the eyes with sunglasses, leading the authors to conclude that in combination with other contextual cues, masks are unlikely to produce serious impairments of children's social interactions. ⁸⁴ A study of 2-year-old children concluded that they were able to recognize familiar words presented without a mask and when hearing words through opaque masks. ⁸⁵ Among children with autism spectrum disorders (ASD), interventions including positive reinforcement and coaching caregivers to teach mask wearing have improved participants' ability to wear a face mask. ⁸⁶⁻⁸⁸ These findings suggest that even children who may have difficulty wearing a mask can do so effectively through targeted interventions.

Conclusions

Experimental and epidemiologic data support community masking to reduce the spread of SARS-CoV-2, including alpha and delta variants, among adults and children. The prevention benefit of masking is derived from the combination of source control and wearer protection. The relationship between source control and wearer protection is likely complementary and possibly synergistic, so that individual benefit increases with increasing community mask use. Mask use has been found to be safe and is not associated with clinically significant impacts on respiration or gas exchange under most circumstances, except for intense exercise. The limited available data indicate no clear evidence that masking impairs emotional or language development in children. Further research is needed to assess masks, particularly to identify the combinations of materials that maximize both their blocking and filtering effectiveness, as well as fit, comfort, durability, and consumer appeal.

As of December 6, 2021

Data were added from studies published since the last update. These studies address the association of mask wearing with new infections, including infections related to SARS-CoV-2 variants of concern. All of these studies demonstrated a benefit.

A section was added on mask wearing among children.

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Important update: Healthcare facilities CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more Science Brief: Community Use of Masks to Control the Spread of SARS-CoV-2 COVID-19 Science Briefs provide a summary of the scientific evidence used to inform specific CDC guidance and recommendations.