After a judge overturned a CDC mandate that US airlines require passengers to wear masks on airplanes, the TSA immediately stopped enforcing masking in airports. One viral video even showed a flight attendant walking down an airplane aisle asking people to throw their masks away. But with Covid cases on the rise again, what does mask-abandonment mean for public health? Even if you don’t have to wear a mask on a plane, should you?
These questions are still frustratingly hard to answer. While science has brought us great advances in pharmaceutical interventions such as vaccines and Covid 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 while around other people. Reducing your own risk also protects others, since you can’t give anyone Covid-19 if you never get infected.
But far too little attention has focused on measuring the impact of public health measures. American public health 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 re-opening the economy. But that was an assumption — and one that hasn’t been rigorously tested.
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 — by about 50%. It’s a different situation, but he thinks it’s reasonable to assume surgical masks masks help somewhat but don’t render a risky situation safe.
In a recent interview, University of Minnesota epidemiologist Michael Osterholm pointed out that mask mandates may give people a false sense of safety. There’s little data on the benefit of cloth masks, and those are the masks that lots of people have been wearing on planes. Worse, lots of passengers remove their masks for large portions of a fight while they eat or drink. If the array of loose-fitting masks most people wear aren’t stopping airborne transmission, people might be taking more risks than they realize.
Air flow is good on airplanes, so the risks aren’t nearly as bad as being in a similar-sized stuffy room full of other people, but there is some danger. Harvard’s Nardell said he’d recommend people who are at higher risk, or just especially cautious, 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 high risk people need to make about whether to take an overseas vacation or a local road trip.
Not all high-risk conditions are alike, so it’s a good idea to consult your doctor before booking a flight, said Leonard Marcus, co-director of the National Preparedness Leadership Initiative at Harvard University. That would be a good idea even with the mask mandate, though he thinks the end of the mandate will make flying somewhat more risky. He also said airplane masking doesn’t have to be all black or white; for example, at times when cases are low, vaccinated people might make a reasonable choice to take off their mask to eat and drink. However, he said right now US cases are edging upward and we could see a new surge with new sub-variants of omicron BA.2.
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, more nudges to get older people boosted 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 is here to stay, and it could be a great benefit to us all to know what helps and what doesn’t.
Bloomberg
