The onset cycle of novel coronavirus varies widely depending on the individual. According to epidemiological surveys, the incubation period of novel coronavirus is 3-7 days, and symptoms of fever, dry cough, and pneumonia will appear about 3-7 days after infection with novel coronavirus. The longest incubation period does not exceed 14 days, but there are individual cases with a longer incubation period of up to 24 days in clinical practice. In addition, due to the different immunity of individuals, some people will quickly develop acute respiratory distress syndrome and even have life-threatening illnesses. Some people will develop respiratory distress after a few days of incubation, which can be cured with treatment. Some people have only a low-grade fever and mild malaise and do not develop symptoms of pneumonia, and can recover spontaneously after a week. Even if you are cured after being infected by the novel coronavirus, you are at risk of being re-infected.