Most common patients infected with novel coronavirus have fever, dry cough, chest tightness, asthma, fatigue, expectoration and possibly hemoptysis. Some patients may have symptoms of upper respiratory tract infection such as nasal congestion, runny nose, sore throat and throat discomfort, as well as anorexia, abnormal taste and loss of sense of smell. A few patients are accompanied by gastrointestinal discomfort such as abdominal pain, diarrhea, nausea and vomiting, and some patients are asymptomatic, which is called asymptomatic infection.

The main characteristics of novel coronavirus are as follows: 1, the incubation period of COVID-19 infection is 1- 14 days, mostly 3-7 days, and the longest reporting period is 24 days. 2. It is highly contagious and can be transmitted from person to person. The basic infection number RO value is about 4. 3, the route of transmission, in addition to the common respiratory droplet infection, but also through contact to spread infection, asymptomatic infected people may also become infected.