CDC Says Vaccinated Can Shed Masks Outside, Except in Crowds

TUESDAY, April 27, 2021 -- Fully vaccinated Americans can now go without masks when walking, jogging or biking outdoors, or when dining with small groups at outdoor restaurants, U.S. health officials announced Tuesday.

The latest guidance, from the U.S. Centers for Disease Control and Prevention, followed growing calls from infectious disease experts to drop mask mandates outside because breezes rapidly disperse airborne virus particles, distancing is easier, and humidity and sunlight dampen the coronavirus' ability to spread.

Even unvaccinated individuals may go without masks when walking, jogging or biking outdoors with household members, the CDC added in its latest guidance.

"Outdoor activity really is a very safe environment. There's very little evidence of viral spread, mask or not," said Dr. Eric Cioe-Pena, director of global health at Northwell Health in New Hyde Park, N.Y. "I applaud the CDC for instituting sensible public health guidance. The advice is not monolithic, but instead acknowledges our evolving science and understanding of COVID."

Despite the loosening of mask guidelines, health officials urged everyone -- vaccinated or not -- to wear masks when attending crowded sporting events, live concerts and parades.

"What's clear is this: masks should be used in the setting of large outdoor gatherings where people are in close proximity for prolonged amounts of time, such as a sporting event or in the setting of a protest or even a rally," said Dr. Robert Glatter, an emergency room physician at Lenox Hill Hospital in New York City.

"A good rule of thumb is that if you are indoors, wearing a mask and maintaining at least 6 feet of distance are essential. If you are outdoors with at least 6 feet of distance, masks are not necessary," Glatter added.

The new guidance aims to help the fully vaccinated return to daily routines while encouraging others to get their shots as soon as they can.

A growing body of evidence suggests that fully vaccinated people are less likely to have asymptomatic infections or transmit the coronavirus to others. Officials don't yet know how long that protection lasts and exactly how much the vaccines protect against emerging virus variants.

Still, "taking steps toward relaxing certain measures for vaccinated people may help improve coronavirus vaccine acceptance and uptake," the guidance stated. "Therefore, there are several activities that fully vaccinated people can resume now, at low risk to themselves, while being mindful of the potential risk of transmitting the disease to others."

Last month, the CDC told Americans who were fully vaccinated they could gather indoors with other fully vaccinated people without wearing masks, and could visit indoors with unvaccinated people under certain conditions.

Dr. Monica Gandhi, an infectious diseases expert at the University of California, San Francisco, is among the experts who have urged the relaxation of mask guidance outdoors, arguing that accumulating evidence shows the low risk of outside transmission.

"Viral particles disperse effectively in the outside air," she told the Washington Post. "With more and more Americans getting vaccinated, I commend the CDC for revising its guidelines to say vaccinated individuals do not need to mask outdoors."

Gandhi noted that the World Health Organization says masks are not necessary outside unless physical distancing, which the WHO defines as about 3 feet, cannot be maintained.

She and others have said it's important for public health officials to provide incentives, such as the ability to go outdoors without masks, as "a great strategy to encourage those who are on the fence to get vaccinated," the Post reported.

The guidance also states that people taking immunosuppressive medications should discuss the need for personal protective measures with their health care providers even if they are fully vaccinated.

Posted: April 2021