According to epidemiological findings, symptoms of pneumonia, such as fever and dry cough, generally appear 3-7 days after infection with novel coronavirus, and the latest onset is currently about 14 days after infection with the virus. Most patients infected with novel coronavirus will develop symptoms about 1 week after infection. Depending on individual resistance, some will develop symptoms such as mild malaise and low fever, which can be cured spontaneously after a week; some will develop symptoms of pneumonia such as high fever and difficulty in breathing, which can be cured after treatment; some will rapidly develop symptoms such as acute respiratory distress syndrome, blood clotting dysfunction, or even death.