Early symptoms of novel coronavirus infection are mainly fever, malaise, and dry cough. A few patients may have upper respiratory tract infection symptoms such as nasal congestion and runny nose, or gastrointestinal symptoms such as diarrhea. Pneumonia may not be present in mild cases, and recovery may occur after a week. Severely ill patients may have moderate to low fever or even no significant fever during the course of the disease, with respiratory distress developing after a week, followed by acute respiratory distress syndrome, septic shock, uncorrectable metabolic acidosis and coagulation dysfunction. In children, the symptoms are relatively mild and require attention once they appear.