A patient adjusts his face mask as he leaves a COVID-19 vaccination site inside the Jacob K. Javits Convention Center, Wednesday, Feb. 3, 2021, in the Manhattan borough of New York. (AP Photo/John Minchillo)

A patient adjusts his face mask as he leaves a COVID-19 vaccination site inside the Jacob K. Javits Convention Center, Wednesday, Feb. 3, 2021, in the Manhattan borough of New York. (AP Photo/John Minchillo)

U.S. CDC study finds two masks are better than one vs. COVID-19

When both exhaling and inhaling heads were double-masked, more than 95% of the particles were blocked

U.S. government researchers found that two masks are better than one in slowing coronavirus spread, but health officials stopped short of recommending that everyone double up.

The Centers for Disease Control and Prevention on Wednesday reported the results of a lab experiment that spaced two artificial heads 6 feet from each other and checked to see how many coronavirus-sized particles spewed by one were inhaled by the other.

The researchers found that wearing one mask — surgical or cloth — blocked around 40% of the particles coming toward the head that was breathing in. When a cloth mask was worn on top of a surgical mask, about 80% were blocked.

When both the exhaling and inhaling heads were double-masked, more than 95% of the particles were blocked, said the CDC’s Dr. John Brooks.

Still, for now, health authorities acknowledge they have their hands full just trying to get more people to wear one mask and wear it correctly.

“The first challenge is to get as many as people as possible masking. And then for those that do mask, to help them get the best benefit out of that mask,” Brooks said.

Brooks said agency officials heard about people donning two masks and wanted to evaluate whether it was beneficial.

The study had many limitations: The researchers used one brand of surgical mask and one kind of cloth mask, and it’s not clear if results would be the same with every product. But it echoes some earlier research that suggests two masks are better than one.

“It works,” Brooks said.

The CDC updated its guidance, saying people can wear a cloth mask on top of a disposable surgical mask “for better fit and extra protection.” If done correctly, the combination can tighten the gaps around the mask’s edges that can let virus particles in, the CDC said.

The agency also said it will take down a make-your-own mask page, which went up last year when masks were in short supply and the CDC was encouraging people to take steps to interrupt viral transmission.

Some Americans have already started doubling up. Experts believe that’s at least partly out of concern about new strains of coronavirus that have been found to spread more easily than the one that has driven the U.S. epidemic for the past year

CDC guidance has evolved over the course of the epidemic.

Mask-wearing has long been common in some countries during respiratory outbreaks, especially in parts of Asia, but not in the United States.

When the COVID-19 crisis began and masks disappeared from store shelves, U.S. health officials actively discouraged the general public from wearing them. “Seriously people – STOP BUYING MASKS!” then-Surgeon General Jerome Adams wrote in a tweet almost a year ago.

Two months later, after it became clear that infected people who did not exhibit symptoms could spread the virus, the CDC began recommending people wear masks in public.

READ MORE: Threat from variants means provinces must be ready to lock down again quickly: Tam

Mask-wearing increased and some places enforced mask mandates, but many Americans continue not to wear them. A recent University of California survey suggested that only about half of U.S. adults wear masks when in close contact with people outside their household.

Discussions about double-masking and higher-quality masks are important, said Dr. Isaac Bogoch, an infectious diseases scientist at the University of Toronto.

“But if a significant proportion of your populations isn’t wearing a mask in the first place, then you’re having the wrong conversation,” he added.

___

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

Mike Stobbe, The Associated Press


Like us on Facebook and follow us on Twitter.

Want to support local journalism during the pandemic? Make a donation here.

Coronavirus

Just Posted

The City of Red Deer sits at 249 active cases of the virus, after hitting a peak of 565 active cases on Feb. 22. (Black Press file image)
Red Deer down to 119 active COVID-19 cases

Province identifies 179 new cases Saturday

Member Terry Parsons’ custom built track vehicle.
Forestburg’s Area 53 Racetrack gears up for action-packed season

Site will also host a portion of the ‘Miles of Mayhem’ event in July

Sabrina Wilde in front of a recently purchased monster truck. Submitted.
Thorsby business women a finalist for 2021 Alberta Women’s Entrepreneurship Award

Sabrina Wilde with Lone Wolf Mechanical is a finalist for the entrepreneurial award.

Grade 12 students at Wetaskiwin Composite High School took place in the annual water fight off school property on June 11, 2021. Shaela Dansereau/ Pipestone Flyer.
Graduating students in Wetaskiwin throw water fight after being told it could result in suspension

Students were told their participation could result in them being barred from graduation ceremonies.

At an outdoor drive-in convocation ceremony, Mount Royal University bestows an honorary Doctor of Laws on Blackfoot Elder and residential school survivor Clarence Wolfleg in Calgary on Tuesday, June 8, 2021. THE CANADIAN PRESS/Jeff McIntosh
‘You didn’t get the best of me’: Residential school survivor gets honorary doctorate

Clarence Wolfleg receives honorary doctorate from Mount Royal University, the highest honour the school gives out

Flowers and cards are left at a makeshift memorial at a monument outside the former Kamloops Indian Residential School to honour the 215 children whose remains are believed to have been discovered buried near the city in Kamloops, B.C., on Monday, May 31, 2021. THE CANADIAN PRESS/Darryl Dyck
‘Pick a Sunday:’ Indigenous leaders ask Catholics to stay home, push for apology

Indigenous leaders are calling on Catholics to stand in solidarity with residential school survivors by not attending church services

“They will never be forgotten, every child matters,” says Sioux Valley Chief Jennifer Bone in a video statement June 1. (Screen grab)
104 ‘potential graves’ detected at site of former residential school in Manitoba

Sioux Valley Dakota Nation working to identify, repatriate students buried near former Brandon residential school

Denmark’s Christian Eriksen receives medical attention after collapsing during the Euro 2020 soccer championship group B match between Denmark and Finland at Parken stadium in Copenhagen, Saturday, June 12, 2021. (AP Photo/Martin Meissner, Pool)
Christian Eriksen in stable condition, Euro 2020 match resumes

Eriksen was given chest compressions after collapsing on the field during a European Championship

As stories of the horrors of residential schools circulate after the Tk’emlups te Secwepemc First Nation announced it had located what are believed to be the remains of 215 children, Grand Chief Stewart Phillip of the Union of B.C. Indian Chiefs said he feels a connection with the former students. THE CANADIAN PRESS/Darryl Dyck
2 sides of the same coin: Ex-foster kids identify with residential school survivors

Grand Chief Stewart Phillip says the child welfare system takes Indigenous children from their families

Airport ground crew offload a plane carrying just under 300,000 doses of the single-shot Johnson & Johnson COVID-19 vaccine which is developed by the Janssen Pharmaceutical Companies at Pearson International Airport during the COVID-19 pandemic in Toronto on Wednesday, April 28, 2021. THE CANADIAN PRESS/Nathan Denette
1st batch of Johnson & Johnson vaccines won’t be released in Canada over quality concerns

The vaccines were quarantined in April before they were distributed to provinces

The arrest south of Winnipeg occurred before Bernier was to arrive at a protest in the city. (Twitter/Maxime Bernier)
Maxime Bernier arrested following anti-rules rallies in Manitoba: RCMP

He’s been charged with exceeding public gathering limits and violating Manitoba’s requirement to self-isolate

Prime Minister Justin Trudeau arrives for the G7 Summit, at the airport in Newquay, United Kingdom, Thursday, June 10, 2021. THE CANADIAN PRESS/Adrian Wyld
Details on Canada’s vaccine sharing plan coming Sunday, up to 100 million doses

Canada’s high commissioner to the UK says details will come after the G7 summit

Most Read