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Tight or double face masks can help limit COVID transmission -- study

Published Feb 11, 2021 08:39 am

Wearing a tight-fitting or two masks can help limit the transmission of the COVID-19, according to a new US study released on Wednesday, Feb. 10, 2021.

APF/ MANILA BULLETIN/ FILE PHOTO

The Centers for Disease Control and Prevention (CDC) study said the transmission of the virus can be reduced by up to 95 percent if both an infected individual and an uninfected individual wear tightly fitted surgical masks or a cloth-and-surgical-mask combination.

"These laboratory-based experiments highlight the importance of good fit to optimize mask performance," the study said.

The effectiveness of cloth and medical procedure masks can be improved by ensuring that they are well fitted to the contours of the face to prevent leakage of air around the masks’ edges, it added.

The study said that by controlling the spread of aerosol drops, the mask experiments showed that an infected person is less likely to transmit COVID, while a non-infected person is less likely to become infected.

Results from the first experiment showed that an unknotted medical mask alone blocked 42 percent of particles from a simulated cough, and the cloth mask alone blocked 44 percent.

But the combination of the cloth mask covering the medical mask blocked 92 percent of cough particles.

In the second test, adding a cloth mask over a medical mask, or knotting and tucking the medical mask to fit better, reduced the cumulative exposure of the unmasked receiver by 82 percent and 63 percent.

Other effective options that improve the fit include using a mask-fitter over a mask, or wearing a sleeve of sheer nylon hosiery material around the neck and pulled up over a cloth or surgical mask, the CDC said.

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