States across the US have dropped their mask mandates this week, worrying Americans who think they’re still needed and cheering people who are ready to go “back to normal.” Both groups need to take a deep breath: Dropping mask mandates isn’t the same thing as ignoring Covid-19.
Masks have been the most visible part of America’s pandemic response, but one of the least consequential. The fact that 500,000 people worldwide died during the omicron surge means it’s time to change tactics, and focus on what went wrong that led to so many hospitalizations and deaths.
Mask mandates are predicated on the effectiveness of “universal masking” in which everyone wears a mask to keep case numbers lower. One of the leaders in proposing universal masking, Monica Gandhi of UCSF, has unfairly been accused of being an anti-masker for talking about the limitations of her own strategy and the much greater importance of vaccination campaigns.
But there’s no avoiding it: The benefits of universal masking have been difficult to quantify. One controlled study in Bangladesh showed a small but statistically significant benefit — among people who consistently used masks, 7.6% got symptomatic infections compared to 8.6% in the control group. Other studies have been inconclusive.
It is intuitive that a barrier ought to prevent germs from being emitted into the air. But if that’s true, why isn’t there more evidence for the benefits of masking two years into the pandemic? Experts associated with The Center for Infectious Disease Research and Policy (CIDRAP) at the University of Minnesota have laid out a more complex analysis: Given the current understanding that the virus is transmitted in fine aerosol particles, it’s likely an infectious dose could easily get through and around loose-fitting cloth or surgical masks.
Many experts say only N95 respirators or similar devices are truly effective at stopping this virus — and some, such as the CIDRAP head Michael Osterholm, have been going public urging people to put less faith in cloth masks and adopt respirators such as N95s. He does not advocate universal N95 use in schools, however, where children are unlikely to be able to wear them consistently or correctly.
Most of the people who were only wearing masks because of the mandate were donning the less effective masks. Those concerned enough to get an N95 aren’t going to stop because it’s not required. Future policies should focus on helping people understand their risks and making sure everyone who wants a supply of N95 masks can get one.
The most visible change will be in stores, and these are not the most dangerous venues. Much riskier are crowded bars or private gatherings where people were already removing their masks to eat and shouting to be heard. Several studies have shown that the louder someone talks, the more particles they expel. Other studies show prolonged exposure to others indoors is much riskier than fleeting exposures.
All those factors may explain why the states with mask mandates haven’t fared significantly better than the 35 states that didn’t impose them during the omicron wave. Rhode Island, where I live, has had a mask mandate since mid-December; nonetheless, we saw our January surge rise far higher than any other state. There’s little evidence that mask mandates are the primary reason the pandemic waves eventually fall — though much of the outrage over lifting mandates is based on that assumption. Many experts acknowledge that the rise and fall of waves is a bit of a mystery, as epidemiologist Sam Scarpino explained to me on my podcast.
What is clear is that states with high vaccination rates have fewer hospitalizations and deaths, and that booster shots are essential for anyone over the age of 65 or at high risk of severe disease.
Megan Ranney, an emergency medicine physician and a dean at the Brown University School of Public Health, says most of her hospitalized patients were unvaccinated or they live in multi-generational homes and got the disease from younger family members who skipped the shots. She sees no problem with the idea of lifting mask mandates when the stress on hospitals has eased.
“It’s absolutely appropriate to relax mask mandates as cases drop below a threshold, particularly in areas with high vaccination and particularly once hospitals are not in crisis mode,” she says. She would have liked to see some states wait a bit longer, though, and says lifting mandates in schools should depend on both case counts coming down and vaccination rates among students getting above 85%. (Vaccination rates are currently at 23% for kids ages five to 11 and 57% for kids 12 to 17.)
In other countries, mask mandates have been imposed and lifted with little or no rancor. Last week I talked to Michael Bang Petersen, a political scientist and psychologist who has been directing a research project on pandemic behavior at Aarhus University in Denmark. There, remarkably, all restrictions were lifted this month with little controversy.
Some of that is due to good communication and trust. “We can see that a clear majority of the population feel that they actually getting clear information from the authorities,” he said.
And Danish authorities have a realistic goal — not minimizing all cases or eliminating the virus but preventing the healthcare system from breaking down. “I think if we look at how it is that the Danish public thinks about coronavirus, they don't think of it as an individual threat … they think of it as a societal threat,” he said.
Americans are not selfish — we think about protecting society too — but we’re deeply divided about what our obligations should be. One way we might ease our tensions is by putting the role of mask mandates in perspective.
Bloomberg
