We lack research data on how masks help us keep covid away
PremiumIt is ridiculous that we still have so little data in support of masks
After a judge overturned a mandate of the US Centers for Disease Control and Prevention (CDC) requiring US airline passengers to wear masks aboard aircraft, transport security systems stopped enforcing masking at airports. One viral video even showed a flight attendant walking down an aeroplane 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 risks associated with flying or the benefits of cloth and surgical masks. We do know that people decrease their own risk of getting sick when they wear an N95 respirator around other people. Reducing your own risk also protects others, since you can’t give anyone covid if you don’t get infected.
But far too little attention has focused on measuring the impact of public health measures. American public health officials simply decided that face coverings would be America’s primary non-pharmaceutical intervention, under the assumption that we needed something to protect people while re-opening the economy. But that was just an assumption—and one that hasn’t been rigorously tested.
Several controlled trials have shown a small benefit from 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 help a bit 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 aeroplanes, so the risks aren’t nearly as bad as being in a similar-sized stuffy room full of others, some of whom may have covid, 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 in decisions that people at high risk need to make while deciding 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 aircraft masking does not 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 yet see another infection surge on account of new sub-variants of Omicron like 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 in America.
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 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. As covid is here to stay, it would be a great benefit to us all to know what helps and what doesn’t.
Faye Flam is a Bloomberg Opinion columnist and host of the podcast “Follow the Science."