There is some chance of being infected when wearing a mask and being with a confirmed case of new crown pneumonia, but the chance of infection is reduced relative to those who do not wear a mask. Data from a Danish study showed that close contact with an infected person resulted in a 66% higher rate of infection in the non-masked test group than in the masked group. The vaccine studied at Oxford University, on the other hand, had a protection rate of only 62%, even with a full dose of two injections. Therefore wearing a mask plays a very important role in outbreak prevention and control. It should be noted that when wearing masks, you should choose medical surgical masks or N95 masks that can effectively prevent viral infections. Ordinary industrial masks, anti haze masks, decorative masks are not effective in preventing viruses. Currently need to closely monitor whether the fever, cough, fatigue and other symptoms, good personal protection to reduce the occurrence of infection. Tip: “New coronavirus pneumonia” and “new coronavirus pneumonia” mentioned in this article were renamed to “new coronavirus infection” on December 26, 2022, as announced by the National Health Commission.