Should we still wear masks if no longer required to fly?

After a judge overturned a CDC mandate that U.S. airlines require passengers to wear masks on airplanes, the TSA immediately stopped enforcing masking in airports. But with COVID-19 cases on the rise again, what does mask-abandonment mean? Even if you don't have to wear a mask on a plane, should you?

While science has brought us advances in pharmaceutical interventions such as vaccines and COVID-19 treatments, it's provided little new information about the value of non-pharmaceutical interventions such as masks.

We know far less than we should about the COVID-19 risks associated with flying or the benefits of requiring cloth and surgical masks. We do know that people decrease their own risk of getting sick when they wear an N95 respirator. Reducing your own risk also protects others.

But far too little attention has focused on measuring the impact of public health measures. Officials simply decided that mandating face coverings would be our primary non-pharmaceutical intervention, under the assumption that we needed something to protect people while reopening the economy. But that was an assumption.

Several attempts at controlled trials showed a small benefit for universal masking with surgical masks — a 10% reduction in cases. Harvard medical professor Edward Nardell says there's good data showing surgical masks in a hospital setting reduced transmission of TB — not COVID-19 — by about 50%. It's a different situation, but he thinks it's reasonable to assume surgical masks masks help somewhat.

Air flow is good on airplanes, so the risks aren't nearly as bad as being in a stuffy room full of other people, but there is some danger. Harvard's Nardell said he'd recommend people who are at higher risk wear a fitted mask such as an N95. This isn't easy to wear for a long flight, and you'd have to avoid the snacks and drinks — so that should figure into decisions that highrisk people need to make about whether to take an overseas vacation or a local road trip.

It's not too late to learn more about the impact of masking and of different types of face coverings. Controlled studies weren't possible during mask mandates. Now researchers could gather data on volunteers who sign up for masked or unmasked flights.

This is not a good time to scale back on research and mitigation efforts. Vaccines didn't end the pandemic as hoped, and new variants continue to pose new threats. Scientists and public health officials should be doing more, not less, to learn how to keep people safer. We need more free tests, more help with getting immune-compromised people antiviral drugs, and more scientific research on which activities and situations pose the biggest threats.

Experts I interviewed earlier in the pandemic said they saw no downside to universal masking and a potential upside, so it seemed reasonable to do it even without much data. It's ridiculous that two years in, we still don't have the data we need to know how valuable masking is — or isn't. COVID-19 is here to stay, and it could be a great benefit to us all to know what helps and what doesn't.