It is possible to be infected with novel coronavirus pneumonia even if you wear a mask, because whether or not you are infectious depends on a variety of factors. Novel coronavirus pneumonia is highly contagious and can be transmitted through the respiratory tract via droplets. The probability of transmission is usually greatly reduced by wearing a mask, such as a surgical mask or a medical N95 mask, which can effectively protect against the new coronavirus pneumonia, and the probability of contracting it is very low. However, if the mask worn is not up to par, such as an ordinary mask or an anti-haze mask, it is generally unable to block the spread of the virus and may still be infectious. Therefore, whether or not NCCP is contagious when wearing a mask depends largely on the effectiveness of the mask.