The incubation period of novel coronavirus is generally 3-7 days, and patients with up to 24 days have been found, but they are isolated cases. Since novel coronavirus is also contagious during the incubation period, it is important to do a good job of isolation and observation when you have just returned from an infected area or when you have symptoms such as fever, dry cough and physical weakness to prevent transmission during the incubation period. If no symptoms of novel coronavirus appear after appropriate time of isolation, the possibility of infection with novel coronavirus can be basically ruled out, as for the physical symptoms of discomfort, they may also be caused by other diseases.