Omicron is mainly characterized by fever, dry cough and malaise. Omicron belongs to a variant strain of C. neoformans, and patients infected with Omicron mainly present with fever, dry cough, and malaise. Some other patients mainly present with conjunctivitis, nasal congestion, runny nose, sore throat, loss of smell and taste, and diarrhea. If the patient’s condition is more severe, dyspnea and/or hypoxemia mostly appear one week after the onset of the disease, and in severe cases, it will rapidly progress to acute respiratory distress syndrome, difficult-to-correct metabolic acidosis, septic shock, coagulation dysfunction, and multi-organ failure. Mild patients show low fever, no pneumonia manifestations; heavy, critical patients may be in the course of the disease for the low fever, or even no obvious fever. Some patients infected with omicron may not develop clinical symptoms. Omicron is a mutated strain of the new coronavirus, which is contagious. When symptoms are suspected, it is important to isolate oneself in time and report to the community and the hospital in a timely manner. Daily to do a good job of diligent disinfection, hand washing, go out and wear a mask. [Tip] In this article, “new coronavirus pneumonia” and “new coronavirus pneumonia” have been renamed to “new coronavirus infection” on December 26, 2022, as announced by the National Health Commission.