Right double masking will increase COVID safety

February 10, 2021 – Wearing a tight-fitting surgical mask or doubling up on masks can significantly reduce COVID-19 transmission and slow the spread of new, more contagious strains, according to a CDC report released Wednesday.

The researchers found that if two people both wear surgical masks that are knotted and flush with their faces, or if both wear a cloth mask over a surgical mask, exposure to virus particles is reduced by more than 95%.

“The data in this report underscores the finding that a good fit can increase the overall effectiveness of the mask,” the authors wrote. “Several simple ways to improve the fit have been shown to be effective.”

A “simulated breath test” shows that surgical masks on their own block block 42% of the COVID-19 particles for the wearer and cloth masks block around 44% of the particles. Wearing a cloth mask over a surgical mask increases protection for the person wearing the masks and blocks 83% of small particles.

While other recent studies looked at “mask assemblers” – a tape that goes over a mask to hold it close to the face – and found that they improve performance, the CDC believes that the best fit is through wearing it A cloth mask is obtained from a covered surgical mask.

US COVID deaths rose in November and, while declining, are still high. Officials have warned that the UK-based variety could ultimately become the dominant strain in the US by March.

These results are reflected in growing concerns about three new, highly contagious COVID-19 variants first identified in the UK, South Africa and Brazil. All three have found their way across US borders.

Regarding the new coronavirus variants, CDC Director Rochelle Walensky, MD, told reporters at a White House briefing Wednesday that the agency currently estimates that 1 to 4% of COVID cases in the US are due to the UK variant, also known as B117.

In the mask study, Walensky said science was already clear that mask requirements can reduce COVID-19 infections and deaths. However, the new CDC study highlights the importance of properly wearing a mask and making sure it fits snugly and firmly over your nose and mouth.

Walensky said that any type of mask provides some protection, “and well-fitting masks performed the best both in blocking emitted aerosols and in exposing aerosols to the recipient.”

Although little was known about mask protectors at the start of the pandemic, increasing research provides clear evidence that they work well. A June article in the journal Physics of Fluids stated that a cough can cause droplets to travel 12 feet in about 50 seconds. With a properly fitting homemade cotton mask made up of multiple layers, these droplets only moved about 2.5 inches.

An April study in Nature Medicine found that surgical masks drastically reduced the transmission of cold and flu droplets. A January publication in TheLancet Digital Health said that an increase in mask wear in a community would more than triple the likelihood of controlling the spread of COVID-19.

Finally, a CDC study published earlier this month found that from March 22 to October 17, 2020, 10 sites in states with mask mandates reported a decrease in COVID-19 hospital stay growth rates of up to 5.5 percentage points. There are currently more than 40 states and territories with mask mandates.

To ensure that the mask is worn correctly, the CDC recommendations include:

• Choose a mask with two or more layers of washable, breathable fabric
• Place the mask over your nose and mouth and secure it under your chin
• Knot the ear loops of a surgical mask where they will attach to the mask, then tuck in the extra material near the face and flatten it (knotted and tucked masks).
• Fit the mask snugly around the sides of your face and pull the loops over your ears or tie the strings behind your head
• If you have to keep adjusting your mask it won’t fit properly and you may need to find a different type of mask or brand.
• Wear your mask under your scarf, ski mask or balaclavain cold weather
• Have a spare mask ready to replace a wet one
• Keep wet reusable masks in a plastic bag until they can be washed