(Vincent Yu | AP) In this Nov. 12, 2019 file photo, people wearing face masks watch pro-democracy protesters in Central, Hong Kong. In 2019, face masks were the signature of Hong Kong’s protesters, who wore them to protect against tear gas and conceal their identities from authorities. These same masks are now ubiquitous around the world -- a hallmark of the spreading coronavirus worn by people from China and Iran, to Italy and America, seeking to protect against the new coronavirus. The vast majority of people recover from the new virus.