An Infectious Disease Expert Explains Why He Thinks It's Safe To Lift Outdoor Mask Mandates

As more people get vaccinated against COVID-19, they're asking more questions about social distancing rules and mask mandates.

In a blog post this week, Dr. Paul Sax, clinical director of the Division of Infectious Diseases at Brigham and Women's Hospital, argued that it's likely time to end the outdoor mask mandates.

Sax joined WBUR's Morning Edition host Bob Oakes to talk about this.

Highlights from this interview have been lightly edited for clarity.

On why he is arguing that it might be time to end outdoor mask mandates

What we've learned a lot in the past year-plus on the science is how the virus is transmitted. And one of the things we've learned, fortunately, is that outdoor transmission is exceedingly rare, and that's because of the unbelievable ventilation of just being outside. It's estimated that being outside offers a hundredfold more ventilation than being inside in an office and maybe a thousandfold more than being inside a typical home. So it's really very safe. Now, I still would recommend that people wear masks outside if they are in a crowded situation. But the kind of mask-wearing that we're seeing now for people walking alone in the street really just doesn't make any sense.

On what outdoor activities he thinks are safe without a mask

Well, what I think we should do is have mandates where the policy follows the strength of the scientific evidence. And I would advise people that if they're walking by themselves, if they're walking their dog, going on a hike, going on a jog, biking, that they really don't need to wear a mask any longer. And they also wouldn't have to do the silly thing, which is they're there on a hiking trail and they're not wearing a mask, and then they see someone coming up to them and they quickly put their mask on and then take it off again. I don't think there's any evidence at all that that particular activity, which is extremely common, does anything but really just sort of — it's almost like a courtesy effort. If we learn that it's really not risky, then maybe we'll stop having to do that.

On whether you should still maintain distance from people outdoors

So if you're outside, I hope you're fully vaccinated. But if you're outside, let's say [the] vaccination status of the people that you're outside with is unknown, then if you're close to someone and you're having a face to face conversation, by all means, we still recommend mask wearing. I also want to say that if people wish to continue wearing masks outside, even after a mask mandate outside is dropped, they're welcome to do so, and I still would encourage it if you are in a crowded setting, such as a concert or a rally or something like that where you don't really have much control over the crowds.

On whether not wearing a mask outdoors places people at greater risk given the current vaccination rate

We are placing people at greater risk by activities like opening restaurants and gyms and having crowded indoor spaces. That's really what puts people at risk, not outdoor activities. Right now, we're in this absurd situation where someone in Massachusetts could be walking outside with someone from their household, both of them wearing a mask, and then they enter a restaurant and dine indoors in a space that they don't know the ventilation of that space and with strangers who are also unmasked. So that is incredibly paradoxical of what we would recommend from a public health perspective.

Many of us still do not recommend indoor dining at all, and yet the restaurants are open for business. For me, that is a much riskier place to catch COVID-19 than walking outside in the fresh air. I also think there might be something motivating in saying to people, you don't need to wear a mask outside. That'll get people outside, which is safer, and also give a sort of glimpse into a post-pandemic life that we hope to be able to see soon.