The initial symptoms of Omicron are mainly respiratory symptoms, gastrointestinal symptoms and systemic manifestations, or there may be no obvious symptoms. 1. Respiratory symptoms: Many cells in the lungs carry a protein called TMPRSS2 on their surface, which helps the virus enter the lung cells. Therefore, the symptoms of Omicron are mainly in the upper respiratory tract. They manifest as cough, sore throat, hoarse throat, nasal congestion, runny nose, sneezing and other symptoms. 2. Gastrointestinal symptoms: The virus enters the digestive tract and damages the mucous membrane of the gastrointestinal tract, resulting in some digestive symptoms, such as nausea, vomiting, diarrhea and so on. 3. Systemic manifestations: after virus infection, it will lead to the release of inflammatory mediators such as leukotrienes, arachidonic acid and prostaglandins, etc., which act on the thermoregulatory center, resulting in systemic symptoms such as fever, night sweats, fatigue and malaise. In addition to the above symptoms, nausea, vomiting, diarrhea and other symptoms can also occur. If the above symptoms occur, it is recommended to go to the hospital to complete the new coronary nucleic acid test, and if the diagnosis is confirmed to be an infected person, it is necessary to isolate and treat the patient according to the local policy.