The new crown outbreak refers to novel coronavirus pneumonia. Patients with novel coronavirus pneumonia may present with fever, malaise, dysfunction of sense of smell, dry cough, etc. In severe cases, respiratory distress and hypoxemia may also occur. New coronavirus pneumonia is caused by new coronavirus infection, which can be transmitted through droplet and contact, and has a certain incubation period. Some patients may have no obvious clinical symptoms. Mild patients may have low-grade fever, malaise, smell and taste impairment, dry cough, etc., and usually have no manifestation of pneumonia. Severe patients may develop respiratory distress and hypoxemia one week after the onset of the disease, and in severe cases, the disease may rapidly progress to acute respiratory distress syndrome, metabolic acidosis, and multi-organ failure, which can be life-threatening. The prognosis of most patients with novel coronavirus pneumonia is good, but a few patients are in critical condition. New coronavirus pneumonia is highly contagious and can lead to epidemic outbreaks. Once unexplained symptoms such as fever, dry cough, and malaise occur, avoid close contact with others and seek medical attention promptly.