We’ve all noticed that fellow shopper at the grocery store with a mask snugged over his mouth — but not his nose. Maybe you’ve also got a neighbor who tugs her mask down to talk. Or perhaps you’ve detoured around groups of barefaced teenagers jostling each other in a park.
Mask use may be mandated in Washington, but compliance varies — and no one knows by how much.
With novel coronavirus infections soaring to their highest levels since the pandemic started, researchers at the University of Washington are conducting the first systematic survey of mask usage in the state. Starting this week in King County, they hope to identify the types of public settings where inconsistent mask-wearing could be contributing to the ongoing explosion of cases. They also want to find out which groups of people, by age and gender, are more or less likely to take the mask mandate seriously.
The goal is to help health officials address problem areas with targeted persuasion and educational campaigns, said Dr. Judith Wasserheit, a leader of the study and chair of the UW Department of Global Health.
“I think we all recognize that COVID-19 infections are exploding, and the data are clear that masks are one of the best prevention tools we have,” she said. “Understanding what’s happening — where people do and don’t use masks — is going to be really important to inform the development of targeted interventions to … help get us out of this pandemic.”
Anecdotal observations and some limited evidence suggests mask usage has been steadily increasing in many parts of Washington, said Brandon Guthrie, an assistant professor of global health and epidemiology who’s part of the research team. Based largely on data from smartphone apps and Facebook surveys, the UW’s Institute for Health Metrics and Evaluation estimated that by mid-November, more than 70% of people in Washington always wore masks when outside of their homes, up from less than 50% in July.
The institute’s modeling suggests that if 95% of Washington residents wore masks regularly, more than 1,400 COVID-19 deaths in the state could be averted by March 1. As of Nov. 26, 2,421 people statewide have died from COVID-19, with 853 of those deaths in King County.
But the UW study will be far more extensive, collecting data in communities across King County, from Shoreline and Southeast Seattle to Tukwila and North Bend. UW student volunteers will park their cars outside a wide range of retail outlets and gathering places — supermarkets, big box stores, convenience stores and neighborhood markets and parks — and make note of who’s wearing masks and who’s not, by gender and approximate age. They’ll also cover transit stations and Sea-Tac Airport’s baggage-claim area, and gather data on the types of masks people are using.
There won’t be any photography or video recording, and no attempts to identify anyone. The scientists have no enforcement power and stress that they are not out to identify scofflaws, shame individuals or alert authorities.
They’re more interested in determining the categories of places where mask usage is lowest and the age groups least likely to wear face coverings.
“One of the things we’re trying to get at is: Are there situations or scenarios or locations where [health departments] should focus their messaging,” said Marty Cohen, assistant chair of the UW’s Department of Environmental & Occupational Health Sciences.
Messages tailored for those under 20 who gather with friends to play Frisbee on Alki beach will be very different than those targeting middle-aged men who shop at hardware stores in rural communities. And if the surveys identify specific types of businesses where mask enforcement is lax, health officials can reach out with advice and assistance, the researchers say.
The survey is sponsored by the Washington Department of Health. Though the work will be done in King County, one of the goals is to develop a template that other counties can use to conduct their own studies, Cohen said.
Masks remain a politically divisive issue, which is one factor in how they are used, Wasserheit said. This month, mask skeptics widely cited the first randomized controlled trial of masks’ ability to protect wearers from infection. The Danish study enrolled about 6,000 people and found the group that wore masks had only a slightly lower chance of becoming infected.
But that study had several limitations, including that only 46% of participants reported wearing masks in all situations where they should. The study also focused solely on protection for the wearer and did not address the role of masks in preventing the spread of virus from infected people to others, said Marissa Baker, director of the industrial hygiene training program at the UW’s Northwest Center for Occupational Health and Safety.
“One of the main reasons for promoting the use of masks is that they protect the community — they protect someone other than the wearer,” she said.
The UW mask survey will run through March and should be able to detect changes in mask-wearing over time, Baker said.
With multiple vaccines on the horizon and people getting sick of pandemic precautions, there’s a temptation to lower the level of what Cohen calls “covigilance,” or the precautions and mindset needed to keep the virus in check.
But vaccines won’t be readily available to everyone until well into 2021, he said.
“Even when there’s a vaccine we’re still going to need to be wearing masks to prevent COVID from spreading throughout the community.”