aamc.org does not support this web browser. Learn more about the browsers we support.

New section


Consensus Guidance on Face Coverings

New section

Updated June 3, 2021

The AAMC has updated its guidance on face coverings following the latest recommendations issued by the Centers for Disease Control and Prevention (CDC).

While America’s health care workforce has played a critical role since the COVID-19 virus infected its first patient in the United States in early 2020, physicians and scientists alone can’t save American lives from being lost to COVID-19. We need a national, comprehensive, coordinated response to the pandemic, which the AAMC has previously described.

Given guidance from the CDC, fully vaccinated individuals (those who are two weeks past their single Johnson and Johnson vaccine dose or their second Pfizer-BioNTech or Moderna vaccine dose) can now refrain from wearing masks indoors and outdoors in most circumstances1. To reduce risk, fully vaccinated individuals are encouraged to continue wearing masks in higher risk settings until a high percentage of the population in their community is vaccinated. Examples of these settings include grocery stores, gyms, movie theaters, and other crowded settings where the vaccination status of others is not known. Fully vaccinated individuals may also consider wearing a mask outdoors when in crowded settings such as concerts, sporting events, and other mass gatherings where not everyone may be vaccinated. Fully vaccinated individuals can safely visit indoors with other fully vaccinated individuals without a mask.

It is important to note that guidance from the CDC does not override mask orders issued by states, counties, or cities. It is the responsibility of every community to keep citizens safe, and mask requirements can vary in different parts of the country. There are times when, for the safety of others, everyone should wear masks. Business owners, public agencies, or other entities may, at their discretion, require all individuals to wear a mask when inside an establishment.

Prior guidance for unvaccinated individuals remains unchanged except that even unvaccinated people can be outdoors without a mask, unless in a crowded outdoor setting like a concert or sports event.

Wearing a mask is one step everyone can take to provide additional protection for themselves, their family, and their community in situations with elevated risk of infection. Clinicians and others working with patients wear masks and require all visitors to clinical sites to do the same regardless of their suspected COVID-19 status. A mask is not always comfortable and previously had not been a part of everyday life in the United States, but science shows that the benefits outweigh the discomfort, particularly when indoors with others whose vaccination status is unknown. While mask mandates have been issued in areas of appropriate jurisdiction, we are asking that state and local leaders — and all Americans — generally encourage that those who remain unvaccinated wear masks indoors, as well as when in close proximity to others in crowded outdoor settings. While vaccinations are safe and effective, they are not 100% effective in preventing infection2. Risk of infection is significantly greater for those individuals who are immunocompromised.

Face coverings are critical for slowing the spread of the coronavirus, particularly indoors, while some people remain unvaccinated. The medical community’s understanding of this novel virus has grown and evolved since March 2020, when efforts to slow the spread were first introduced. While we still have more to learn, our understanding of effective practices for prevention has grown tremendously. Initial evidence of the effectiveness of face coverings was substantiated through studies conducted early in the pandemic, and continued evidence strongly supports face coverings as a way to decrease transmission. A study by the CDC followed up with 139 clients of coronavirus-positive hair stylists and found no symptomatic secondary cases; both parties had worn masks during the appointment.3 A study in Health Affairs examined the natural experiment of states’ mask mandates on community spread of COVID-19. The study estimates that, by late May 2020, between 230,000 and 450,000 potential COVID-19 cases were averted by the imposition of state mask mandates.4

Reinforcing the importance of prevention measures beyond monitoring symptoms and accelerating the distribution of vaccines, including wearing face coverings in some settings, is essential. Evidence shows that unvaccinated people can unknowingly spread the coronavirus because they may be infected and still asymptomatic, are not yet manifesting their symptoms, or have mild symptoms. One study by the CDC found that of the 1,000 infected service members on the Navy ship USS Theodore Roosevelt, 1 in 5 had no symptoms and many had only mild symptoms.5 Wearing a face covering is one step most people can take to protect themselves, their loved ones, and the most vulnerable in their community.

The latest research reinforces that well-fitting masks can help reduce the risk of virus transmission between individuals, allowing longer exposure while minimizing risk. Multilayer, well-fitting cloth masks; “double masking” 6; well-fitting N95s; and other masks such as KF94s can all reduce an individual’s exposure. As knowledge grows about the virus, its methods of spread and transmission, and the effectiveness of vaccines, these guidelines will be regularly reevaluated and updated.

New section

Do’s for Unvaccinated Individuals

  • DO take a face mask with you when entering a public setting. Before you leave your home, check that you have your wallet, keys, phone, and mask.
  • DO cover your mouth and nose with a face mask to stop the spread of COVID-19.
  • DO wear a well-fitted face covering with no gaps around your nose and chin. If using a medical procedure mask, minimize any gaps by knotting the ear loops and tucking and flattening any extra mask material.7 
  • DO wear a mask with a nose wire.
  • DO wear a cloth mask with at least two layers (three layers when possible).
  • DO consider wearing a KF94, N95, or equivalent Food and Drug Administration (FDA) or NIOSH-approved mask in high-risk settings for maximum protection.
  • DO consider wearing a cloth mask over a medical procedure mask in high-risk settings if you don’t have a specialized high-quality mask like a KF94 or N95.
  • DO double-check any medical-grade mask purchases against the FDA’s list of approved masks.
  • DO wear a face mask indoors around people who are not members of your household unless you are fully vaccinated, in a small gathering, and limiting nonhousehold members to one household. (Everyone 2 years of age and older.)
  • DO wear a mask outdoors when you expect to be in a crowded setting. 
  • DO wear a mask outdoors when you expect to be in a crowded setting DO roll down the window of a car when sharing a ride or traveling with others who are not members of your household if you or others are unvaccinated.
  • DO wash your cloth face covering frequently.


  • DON’T forget to wear a face covering and stop the spread. Protect yourself and others.
  • DON’T leave your home without a face mask.
  • DON’T touch the front of your mask.
  • DON’T wear the face covering under your nose.
  • DON’T share your mask with others.
  • DON’T combine two disposable masks.

If You Are Fully Vaccinated

  • Fully vaccinated individuals can safely be outside without a mask except when at mass gatherings where people are more likely to spread viral particles in close proximity (e.g., concerts, rallies, sporting events).
  • While some people may be comfortable with their risk indoors without a face covering, we recommend wearing masks indoors (even if vaccinated) if the vaccination status of others is unknown. Examples of these indoor settings include grocery stores, gyms, and particularly settings with large crowds like concerts, rallies, and sporting events. In an indoor setting where everyone is vaccinated, it is reasonably safe to remove face coverings. 

Consensus Guidance on Face Coverings

In regions where community spread is significant and/or not falling significantly, wearing face coverings indoors should be mandatory for unvaccinated individuals and continues to be the safest option for vaccinated individuals if the vaccination status of everyone present is unknown. The following practices are recommended:

  • Well-fitted face coverings that minimize gaps around the nose and chin are important. Loosely folded face masks and bandana-style coverings are better than no coverings; however, they still allow for the smallest aerosolized respiratory droplets to be dispersed.8
  • Wear face coverings with at least two layers (three layers when possible). Additional protection can be provided by wearing high quality, well-fitting masks with multiple layers of fabric or by wearing two well-fitting masks. If two masks are worn, the mask worn closest to the face should be a disposable mask, and the outer mask should be a cloth face covering.7 In July 2020, a study found that a double-layer cloth face covering was significantly better at reducing the droplet spread caused by coughing and sneezing than a single-layer one.9 Further research, published in February 2021 by the CDC, found that wearing a cloth mask over a medical procedure mask — or in the case of a medical procedure mask, knotting the ears loops together where they attach to the mask and then tucking in and flattening the resulting extra mask material — increases overall mask efficiency.6


  • Prior to the availability of safe and effective vaccines for adults and adolescents ages 12-17, the CDC had recommended that “all people 2 years of age and older wear a cloth face covering in public settings and when around people who don’t live in your household, especially when other social distancing measures are difficult to maintain.”10 This guidance has been relaxed for vaccinated individuals.
  • The use of face coverings is critically important indoors for unvaccinated individuals, as compared to outdoors. Superspreader events, in which an infected individual causes many subsequent infections, are likely to occur indoors.11
  • All businesses open to the public, no matter how limited, may insist all customers be masked while indoors.
  • Wear face coverings when indoors, even when 6 feet apart, if not with household members (unless you are fully vaccinated or you are only in the room with members of one other household). Some studies suggest that smaller droplets, known as aerosols, can remain in the air longer, though how long is not yet known.12


  • Prior to the availability of safe and effective vaccines for adults and adolescents ages 12-17, the CDC had recommended that “all unvaccinated people 2 years of age and older wear a cloth face covering in public settings and when around people who don’t live in your household, especially when other social distancing measures are difficult to maintain.”10
  • Face coverings are unnecessary outside in non-enclosed spaces for vaccinated and unvaccinated individuals, unless in a crowded area such as a concert or sporting event. 

State and local officials should support the distribution of masks for people experiencing homelessness, people who are incarcerated, and other vulnerable populations.

As the level of COVID-19 community spread reaches sufficiently low levels, face coverings may become optional for everyone. “Low levels” can be defined as low regional spread, no national hot spots that could seed the local ecosystem, and adequate contact tracing so all contacts of infected individuals can be identified and quarantined.

Face coverings are only one measure to prevent the spread of infection. Vaccinations are critical to our safety, and frequent hand-washing and social distancing practices should be employed until more people are fully vaccinated.

If all Americans work together, we can protect our communities and continue reopening our schools and economy. Please join health care leaders in encouraging your family, friends, and community to get vaccinated and — until then — to at least wear a well-fitted face covering every time they come within 6 feet of someone outside their household.



The AAMC Research and Action Institute appreciates the expertise of the following individuals in developing this guidance:
Atul Grover, MD, PhD, executive director, AAMC Research and Action Institute
Ross McKinney Jr., MD, chief scientific officer, AAMC
Sheila Burke, MPA, RN, adjunct lecturer in public policy, Harvard Kennedy School
Ashish Jha, MD, MPH, dean, Brown University School of Public Health; professor of health services, policy, and practice
Megan Ranney, MD, MPH, associate professor of emergency medicine; assistant dean of Brown Institute for Translational Sciences; director of the Brown-Lifespan Center for Digital Health; associate professor of health services, policy and practice

The AAMC also thanks the following individuals for helping to develop this document:
Laura Pincus, MHA, manager, strategy and planning, AAMC Research and Action Institute
Amanda Field, PhD, former senior science policy specialist, AAMC


  1. Centers for Disease Control and Prevention. Interim Public Health Recommendations for Fully Vaccinated People. Updated May 28, 2021. Accessed May 28, 2021. https://www.cdc.gov/coronavirus/2019-ncov/vaccines/fully-vaccinated-guidance.html.
  2. Pilishvili T, Fleming-Dutra KE, Farrar JL, et al. Interim Estimates of Vaccine Effectiveness of Pfizer-BioNTech and Moderna COVID-19 Vaccines Among Health Care Personnel — 33 U.S. Sites, January–March 2021. MMWR Morb Mortal Wkly Rep. ePub: 14 May 2021. doi: 10.15585/mmwr.mm7020e2.
  3. Hendrix MJ, Walde C, Findley K, Trotman R. Absence of apparent transmission of SARS-CoV-2 from two stylists after exposure at a hair salon with a universal face covering policy — Springfield, Missouri, May 2020. MMWR Morb Mortal Wkly Rep. 2020;69:930-932. doi: 10.15585/mmwr.mm6928e2.
  4. Lyu W, Wehby G. Community use of face masks and COVID-19: evidence from a natural experiments of state mandates in the US [published online ahead of print June 16, 2020]. Health Aff. doi: 10.1377/hlthaff.2020.00818.
  5. Payne DC, Smith-Jeffcoat SE, Nowak G, et al. SARS-CoV-2 infections and serologic responses from a sample of U.S. Navy service members — USS Theodore Roosevelt, April 2020. MMWR Morb Mortal Wkly Rep. 2020;69:714-721. doi: 10.15585/mmwr.mm6923e4.
  6. Brooks JT, Beezhold DH, Noti JD, et al. Maximizing Fit for Cloth and Medical Procedure Masks to Improve Performance and Reduce SARS-CoV-2 Transmission and Exposure, 2021. MMWR Morb Mortal Wkly Rep. 2021;70:254–257. doi: 10.15585/mmwr.mm7007e1.
  7. Centers for Disease Control and Prevention. Improve How Your Mask Protects You. Updated Feb. 13, 2021. Accessed March 2, 2021. https://www.cdc.gov/coronavirus/2019-ncov/your-health/effective-masks.html.
  8. Verma S, Dhanak M, Frankenfield J. Visualizing the effectiveness of face masks in obstructing respiratory jets. Phys Fluids. 2020;32,061708. doi: 10.1063/5.0016018.
  9. Bahl P, Bhattacharjee S, de Silva C, Chughtai AA, Doolan C, MacIntyre CR. Face coverings and mask to minimise droplet dispersion and aerosolisation: a video case study [published ahead of print July 24, 2020]. Thorax. doi: 10.1136/thoraxjnl-2020-215748.
  10. Centers for Disease Control and Prevention. Considerations for wearing masks. Updated July 16, 2020. Accessed July 31, 2020. https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/cloth-face-cover-guidance.html.
  11. Hamner L, Dubbel P, Capron I, et al. High SARS-CoV-2 attack rate following exposure at a choir practice — Skagit County, Washington, March 2020. MMWR Morb Mortal Wkly Rep. 2020;69:606-610. doi: 10.15585/mmwr.mm6919e6.
  12. Prather KA, Wang CC, Schooley RT. Reducing transmission of SARS-CoV-2. Science. 2020;368(6498):1422-1424. doi: 10.1126/science.abc6197.

This is a publication of the AAMC (Association of American Medical Colleges). The AAMC serves and leads the academic medicine community to improve the health of all. The AAMC Research and Action Institute is a “think and do” tank that builds upon a long-standing AAMC strength of conducting and disseminating cogent research and analyses and informing and transforming practice and policy in U.S. health care. Learn more at aamc.org.

© 2021 Association of American Medical Colleges. May be reproduced and distributed with attribution for educational or noncommercial purposes only.