GUAGZHOU, CHINA - JANUARY 22: Citizens wear masks to defend against new viruses on January 22,2020 in Guangzhou, China.The 2019 new coronavirus, known as "2019-nCoV", was discovered in Wuhan virus pneumonia cases in 2019, and the virus was transmitted from person to person. Currently, confirmed cases have been received in various parts of the world. (Photo by Stringer/Anadolu Agency via Getty Images)