When it Comes to Homemade Masks, the Number of Layers Matters, Study Says

'The main message is that the design of your cloth mask matters'

When it Comes to Homemade Masks, the Number of Layers Matters, Study Says

With medical grade masks still in short supply and badly needed at hospitals and other care centers, many Americans have turned to a variety of other options to help slow the spread of COVID-19, from hand-sewn facial coverings to bandanas and everything in between. But it turns out that when it comes to preventing viral transmission, not all masks are created equal, according to a new study.

In the study, , researchers pitted three kinds of facial coverings against one another: a single-layer “no sew” mask, a two-layer variety made to specifications from the U.S. Centers for Disease Control and Prevention (CDC), and a three-layer surgical mask. Using LED lights, a high-speed camera and a healthy volunteer willing to have their nose repeatedly ticked with a tissue, each variety of facial covering was tested to see which best contained droplets generated from speaking, coughing and sneezing, with the idea that better containment suggests better efficacy in terms of curbing transmission.

“The COVID-19 pandemic and the need for community face masks has raised questions about whether you can just throw a scarf over your face, or whether you should use a better designed cloth mask,” says Raina MacIntyre, a professor of global biosecurity at the University of New South Wales Sydney, and one of the study’s authors.

The result? The surgical mask did the best job overall, but the two-layer CDC mask was still “significantly better” at containing droplets than the single-layer covering. However, the researchers added, “even a single-layer face covering is better than no face covering.”

The results were somewhat unsurprising. Surgical masks are made of multi-layered polypropylene with a water-resistant outer layer, and they’re regulated based on their ability to catch droplets, MacIntyre explains. And the researchers knew from prior studies that cloth masks with more layers generally perform better. In truth you probably need at least 3 layers,” says MacIntyre. Other factors, like the material, design, fit, and how frequently a mask is washed, also make a difference.

This new study follows a similar effort last month, which found that commercially available cone-style masks and quilted, multi-layer homemade masks that were properly fitted did the best job of containing respiratory droplets, while “loosely folded face masks” and bandanas “provide minimal stopping capability for the smallest aerosolized respiratory droplets.”

Still other studies have the need for facial coverings abundantly clear. Research published in June that mask mandates in U.S. states were associated with faster declines in daily COVID-19 case growth, estimating that mask rules prevented up to 450,000 cases through late May. A different also published in June, predicted that the U.S. could avoid more than 30,000 coronavirus-related deaths though October if at least 95% of people wear masks in public, while found that mask wearing could reduce transmission risk from about 17% to roughly 3%.

Of course, the comparative efficacy of various types of facial coverings doesn’t matter if people aren’t covering their faces to begin with. While some cities and states have issued mandatory mask rules, many have not, and the Trump Administration has been reluctant to issue a national mandate. The issue has been politicized across the U.S., perhaps best illustrated by Georgia governor Brian Kemp’s July 16 lawsuit challenging Atlanta’s mask rules and other restrictions despite a worsening outbreak across the state.

Still, most registered U.S. voters now support statewide mask mandates, according to a Politico poll released Wednesday. For those committed to wearing face coverings in order to help keep themselves and others safe, it’s important to know that just tucking your face into your t-shirt might not cut it.

The main message is that the design of your cloth mask matters—more layers is better than just one layer,” says MacIntyre. She recommends making masks with a water-resistant fabric, like polyester, for an outer layer, as well as having at least three layers and ensuring a good facial fit. “Most importantly,” she adds, “always use a clean mask and wash your used mask daily.”

Source : Time More   

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Trump Now Says Some Schools May Need to Delay Reopening as Coronavirus Surges Continue

It marks a shift from Trump’s previous demand for a full reopening of the nation’s schools

Trump Now Says Some Schools May Need to Delay Reopening as Coronavirus Surges Continue

Softening his earlier stance, President Donald Trump on Thursday acknowledged that some schools may need to delay their reopening this fall as the coronavirus continues to surge.

It marks a shift from Trump’s previous demand for a full reopening of the nation’s schools. In recent weeks, Trump has said that it’s safe to open schools and that Democrats have opposed it for political reasons.

But speaking at a White House news conference, Trump said districts in some virus hot spots “may need to delay reopening for a few weeks.” He said the decision will fall to governors.

Even as he tempered his position, though, Trump insisted that every school should be “actively making preparations to open.” Students need to be in school buildings to prevent learning setbacks, he said, and to access meal programs and mental health services.

As long as they have necessary measures in place, he added, “many school districts can now reopen safely.”

Trump has made opening schools a key priority as he looks to restart the economy. Students need to return to the classroom so their parents can return to work, he has said.

His push has at times put him at odds with his own health officials. Earlier this month, he said school guidelines from the Centers for Disease Control and Prevention were too tough, prompting the agency to promise updated guidance.

The CDC on Thursday added new information to its website on opening schools, but it did not appear to remove any of its earlier suggestions. Much of the new material emphasized the importance of reopening schools, echoing many of Trump’s arguments.

The updated guidance urged school leaders to work with local officials to make decisions about the fall, taking into account the virus’s rate of transmission in the area. It laid out a range of measures depending on the level of spread. If there’s minimal or moderate spread, it recommends social distancing, masks and increased sanitation.

But in areas with substantive and uncontrolled spread, it says, school closure is an “important consideration.” “Plans for virtual learning should be in place in the event of a school closure,” the CDC said.

Some of the nation’s largest districts have already rejected the idea of a full reopening. The Los Angeles and San Diego districts plan to keep classes online this fall, while New York City’s schools plan to offer a mix of online and in-person instruction.

Education Secretary Betsy DeVos has said that students should be in the classroom every day if their families want and that any alternative fails students and taxpayers.

In many states, education leaders have said they want to return to school but lack the funding to implement safety measures. A group of state education chiefs has said U.S. schools would need more than $200 billion to prepare for a fall reopening.

Trump on Thursday said he’s asking Congress to provide $105 billion in education funding as part of the next virus relief bill. It’s meant to help schools reduce class sizes, hire teachers, rearrange spaces and provide masks, he said.

But if a local district doesn’t open, Trump said, the money should be steered to parents so they can pursue other education options.

“If schools do not reopen, the funding should go to parents to send their children to the public, private, charter, religious or home school,” he said. “All families should be empowered to make the decision that is right for their circumstance.”

Responding to his proposal, the president of one of the nation’s largest education unions said Trump was “sowing seeds of chaos and confusion so he can fulfill his and Betsy DeVos’ dream of privatizing and voucherizing public education.”

“He’s provided no plan and no funding and has ignored the health experts,” said Randi Weingarten, president of the American Federation of Teachers. “Teachers won’t let him get away with it.”

Source : Time More   

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