During the incubation period of novel coronavirus patients themselves are asymptomatic and the incubation period is contagious. Infected patients may develop severe clinical symptoms, so many people who are usually asymptomatic are not advised to go out and are recommended to be isolated at home. Residents returning from infected areas or those who have been in contact with febrile patients should also be observed for changes in body temperature or the appearance of new onset of coughing and coughing.