Illustration of a COVID-19 microbe expanding.
Illustration: PGN

What you need to know

  • The overall risk of infection is higher now because of BA.5’s increased transmissibility and ability to evade existing immunity.
  • Being outdoors remains safer than being indoors due to increased ventilation.
  • Evaluate the outdoor circumstance as well as your own risk level to decide if you should wear a mask.

For many Americans, this summer has been filled with the travels and gatherings they missed out on over the last two pandemic summers. But it has also been somewhat dampened by the rise of BA.5. As the Omicron subvariant continues to keep daily cases in the U.S. at an average of around 120,000, some people may be wondering if outdoor activities are as safe as they used to be.

Are more people getting infected outdoors than before? 

The risk of getting infected outdoors was never zero. But it does seem like outdoor transmission is becoming more common, at least anecdotally, says Linsey Marr, a professor of civil and environmental engineering at Virginia Tech who studies viruses in the air. 

Increased outdoor transmission is likely because BA.5 is causing overall COVID-19 transmission to become more prevalent. As variants become more transmissible and better at evading existing immunity, the risk of getting infected under any circumstance will be greater.

In other words, the virus is not specifically getting better at spreading outdoors—it’s becoming more contagious in general. “At this point, it’s safe to say that indoor transmission and people letting their guard down is what’s driving these waves,” says Kristen Coleman, an assistant research professor at the University of Maryland School of Public Health.

Is it still safe to socialize outdoors without a mask?

Experts largely agree that, in most cases, it’s safe to interact and socialize outdoors without a mask, even with the spread of Omicron subvariants. The outdoor environment has maximum ventilation, which means the virus is less likely to make its way from one person to another.

“One way to think about it is if you’re indoors, it’s like you’re putting a drop of dye into a glass of water—it’s confined,” Marr says. “If you’re outdoors, it’s like you’re putting a drop of dye in the ocean—it’s going to rapidly become very diluted.”

The risk of contracting COVID-19 outdoors is much lower than it is indoors. However, Katrine Wallace, an epidemiologist at the University of Illinois at Chicago, emphasizes that no single layer of mitigation—whether it’s masks, vaccines, or ventilation—is 100 percent effective.

“Being outside does not automatically make an activity safe,” Wallace says. “Going to brunch with three friends outside is less risky than going to Lollapalooza [a music festival], where you’re still outside but you’re body-to-body with others and have people breathing all over you.” 

Should I change my behavior outdoors now that BA.5 is around?

The answer depends on each individual and their risk tolerance. What’s at risk if you do get infected? Are you vulnerable to severe disease? Do you want to minimize the risk of getting long COVID? Do you have an event coming up that you don’t want to miss? 

By evaluating both the outdoor circumstance as well as your own risk level, you can determine whether to take additional preventative measures, such as wearing a mask or social distancing.

Coleman says she continues to feel safe outdoors without a mask on, though she has not attended any crowded outdoor events. “I’m quite relaxed outdoors,” she says. “Indoors is when I wear an N95 all the time around people, unless there’s substantial ventilation, filtration, and germicidal UV.”

Marr feels similarly. She says she has been comfortable engaging in social activities outdoors without a mask but has not attended any crowded concerts since the pandemic began.

Wallace says she has always been more cautious and chooses to wear a mask outdoors even though she is up to date on her COVID-19 vaccines. “As much as I can protect myself, I will,” Wallace says. “I don’t mind being the only person wearing a mask—it doesn’t really bother me.”

What factors should I consider when deciding whether to wear a mask outdoors?

The number of people at an outdoor event is a key factor to consider. Large gatherings like concerts, sports events, and parties are higher risk than small gatherings with people you know. Depending on your risk tolerance, you may want to wear a mask in crowded outdoor settings.

The outdoor environment itself also matters. An outdoor tent, for example, can impede ventilation and increase the risk of transmission.

Community transmission is another factor to consider when evaluating risk. However, Marr notes that the CDC’s COVID-19 Community Levels tool no longer provides a full picture of transmission risk due to the prevalence of unreported at-home tests.

“There were instances of outdoor transmission that happened earlier in the pandemic with earlier variants as well, so it’s only plausible that if people are dropping their guard and BA.5 is more transmissible and can evade immunity, then any situation is going to be riskier than it was before,” Coleman says.