The delta strain is one of the major new crown mutants in the current global new crown epidemic, first identified in India and now spreading to several countries. Patients infected with the Delta strain have atypical symptoms. The onset of the disease may be preceded by malaise, abdominal pain, bloating, diarrhea, drowsiness, weakness, impaired sense of smell, and redness of the eyes. As the disease progresses, symptoms such as fever, nasal congestion, runny nose, and sore throat may develop, making it more likely to become severe. The Delta strain is characterized by faster transmission, greater infectivity, higher viral load, shorter incubation period, and faster onset. Some patients can progress to severe disease in 3-4 days, with respiratory distress, cyanosis, and even shock and coagulation dysfunction, which require attention. Patients who present with these manifestations, or who have a history of close contact with confirmed patients, or who have a history of travel in areas with a high risk of neoconiosis, need to be vigilant, report to their community, street, or designated hospital, and be promptly isolated. The general population should also be aware that avoiding crowded places as much as possible, timely vaccination against New Coronas, washing hands regularly, wearing masks, and maintaining social distance have a preventive effect against the Delta strain.