CDC Eases Outdoor Mask-Wearing Guidelines for Small Groups

More than 90 percent of documented Covid-19 cases are sparked by transmission indoors

A group of men wearing protective masks walk in Midtown on April 10, 2021 in New York City.
The majority of documented Covid-19 transmission has taken place indoors, with less than ten percent occurring outdoors, per the Associated Press. Photo by John Lamparski/Getty Images

On Tuesday, the Centers for Disease Control and Prevention announced new guidelines for outdoor mask-wearing, which has been largely required amid the Covid-19 pandemic.

The new recommendations say both vaccinated and unvaccinated people may be safe without a mask while walking outdoors with people from their own household or with a group of vaccinated people. In larger groups with multiple households, the recommendations differ between vaccinated and unvaccinated individuals. At crowded outdoor events, and most indoor activities with people from multiple households, the CDC recommends that everyone wear a mask.

“Today, I hope, is a day when we can take another step back to the normalcy of before,” says CDC Director Rochelle Walensky at a press conference, reports Mike Stobbe for the Associated Press. “Over the past year, we have spent a lot of time telling Americans what you can’t do. Today, I am going to tell you some of the things you can do, if you are fully vaccinated.”

The decision comes as just over 40 percent of people in the United States have received at least one dose of a two-part Covid-19 vaccine, and 29 percent are fully vaccinated, meaning that two weeks have passed since they received the final dose of their vaccine, per the New York Times' vaccine rollout tracker. Three Covid-19 vaccines have been authorized in the United States. The Moderna and Pfizer/BioNTech vaccines require two doses given a few weeks apart, while the Johnson & Johnson vaccine is given as one dose.

“I welcome less restrictive guidelines about masking outdoors,” says Virginia Tech aerosol scientist Linsey Marr to Roni Caryn Rabin and Emily Anthes at the New York Times. “We know that transmission outdoors is much less likely to occur than indoors, because the virus cannot accumulate in the air outdoors. It’ll become rapidly diluted.”

According to the CDC’s new guidelines, people who have been fully vaccinated against Covid-19 may safely attend small outdoor gatherings with a mix of vaccinated and unvaccinated people without wearing masks. They may also safely go maskless when dining at outdoor restaurants with friends from different households. But for people who have not been fully vaccinated, the CDC recommends masks in both of these scenarios.

“The timing is right because we now have a fair amount of data about the scenarios where transmission occurs,” says Northwestern University epidemiologist Mercedes Carnethon to the Associated Press. She adds “the additional freedoms may serve as a motivator” for more people to get vaccinated.

The CDC released guidance at the beginning of March that stated people who are vaccinated against Covid-19 could safely gather with each other indoors in small, private gatherings, and visit with unvaccinated people from one other household. The new guidance recommends everyone should wear masks in shared indoor spaces like salons, public transportation, indoor gatherings with many households, indoor restaurants and exercise studios. The majority of documented Covid-19 transmission has taken place indoors, with less than ten percent occurring outdoors, per the Associated Press. At crowded outdoor settings like live music or sports venues, the CDC recommends everyone wear masks.

“The examples today show that when you are fully vaccinated, you can return to many activities safely … and begin to get back to normal,” said Walensky during the press conference, per the Washington Post’s Lena Sun. “And the more people who are vaccinated, the more steps we can take toward spending time with people we love, doing the things we love to enjoy. I hope this message is encouraging for you. It shows just how powerful these vaccines are.”