According to the current epidemiological investigation, the incubation period of the virus is 1- 14 days. According to the latest Diagnosis and Treatment Plan for Infected Pneumonia in novel coronavirus, based on the current epidemiological investigation, the incubation period of COVID-19 pneumonia virus is 1- 14 days, mostly 3-7 days.
In other words, the virus did not attack the immune system immediately after it entered the human body. It will slowly lurk, infect cells and replicate more viruses until we have symptoms of infection, such as fever, dry cough, fatigue and so on. The obscenity development process of the virus is 1- 14 days based on the epidemiological incubation period. Of course, there are also some cases that have been ill for more than 20 days or even longer, but most of them have symptoms within 14 days.