Originally health officials claimed wearing a mask was unnecessary for those not infected with COVID-19, but that changed when scientists discovered people could be infected with and spread the virus without showing symptoms.
Now, the CDC states if masks are widely used when in public, the number of infections would be reduced. The Lancet examined 172 studies on ways to prevent the virus from spreading and found that wearing masks significantly reduced the chance of transmission. When covering the mouth and nose, cloth masks reduce droplet spray when the wearer coughs, sneezes, talks or yells.
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