Why U.S. Advice on Wearing Masks Became ‘On Again’

(Bloomberg) -- Advice from U.S. authorities on the need for face masks has flipped back and forth since Covid-19 took hold in 2020. In May, the Centers for Disease Control and Prevention said immunized Americans could ditch their masks in most settings. It’s now reversed course amid a rise in cases caused by the more transmissible delta variant.

1. What’s the latest advice?

For everyone, even if they are immunized, to wear masks indoors if they are in parts of the country where infections are surging. This is an effort to help prevent the spread of the delta strain, which is highly contagious and has shown itself to be adept at evading some of the protection provided by vaccines. Rochelle Walensky, the director of the CDC, said it now appears that some vaccinated people infected with the delta variant can transmit the virus to others. The CDC also recommends that countrywide, teachers, staff, students and visitors to schools wear masks indoors, regardless of their vaccination status.

2. What are the implications for Americans?

The CDC guidance is exactly that: guidance. Adoption and enforcement of that advice is up to state and local governments, employers and local businesses. The White House, for instance, has told staff they must again wear masks. State policies on masks span the gamut. Eight states including California, Illinois and New York still require people who are not fully vaccinated to wear face coverings in most indoor public settings, while at least eight others (including Florida and Texas) have taken steps to keep even their cities, counties and school districts from instituting their own mask rules, according to a tally kept by AARP, the U.S. nonprofit formerly known as the American Association of Retired Persons.

3. What was the previous advice?

In the early days of the pandemic, the CDC went so far as to discourage widespread use of masks, in part to preserve supplies for health workers. Eventually, authorities urged all Americans to wear face coverings to contain the spread of the virus. One of President Joe Biden’s first acts after assuming office in January 2021 was to break with his predecessor by issuing a nationwide mask mandate, focused on public transportation and federal workers. In May, the CDC told vaccinated Americans that they could ditch their masks in most settings, even indoors and in large groups. That advice cited growing evidence beyond initial clinical trials that vaccines were effective, including against variants, and that fully vaccinated people were at low risk of spreading the coronavirus to someone else. The loosening did not apply to planes, buses, trains and other forms of public transportation, transportation hubs, health-care settings, correctional facilities or homeless shelters. There was also no change to the recommendation of masks for partially vaccinated people -- those less than two weeks from having received their final dose -- or who haven’t gotten vaccines, including kids too young to qualify for them.

4. What have other countries done?

England dropped laws requiring people to wear face coverings indoors or on public transport in July although the operator of London’s underground rail network still requires them for travelers. The European Centre for Disease Prevention and Control relaxed its mask-wearing guidelines for fully vaccinated people in April, saying they are at low risk of contracting or spreading the virus, but it suggested that even vaccinated people continue to wear masks in public spaces or indoors with people from other households. In June, Israel re-imposed a mandate to wear masks indoors in response to a rise in cases.

The Reference Shelf

• Related QuickTakes on the delta variant, mask guidance around the world, coronavirus variants, Covid among the vaccinated, and vaccine mandates.
• The CDC’s most recent guidance and suggestions on safe activities for vaccinated and unvaccinated people.
• A review of the evidence on face masks and coronavirus transmission published in the Proceedings of the National Academies of Sciences.

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