Frequent colds are associated with decreased body resistance and viral infections, and are more likely to occur in people with chronic respiratory diseases or in the elderly and frail. 1. Decreased resistance: In the event of rain, cold, mental stress or excessive fatigue and other triggering factors, the body’s resistance is low, and pathogens present in the respiratory tract multiply rapidly, so the body catches a cold. 2. Viral infections: there are chronic underlying diseases such as chronic respiratory lesions (such as sinusitis, rhinitis) and the elderly and frail, the virus is prone to invade the nasal mucosa, colds can often occur. In addition, some people with immunodeficiency diseases may also catch colds frequently. After the occurrence of a cold, the diagnosis can be made by physical examination, routine blood tests, imaging tests such as lung CT, pathogenetic tests such as nasal swabs and other relevant tests. After catching a cold, it is recommended to consult a doctor in a timely manner, use medication under the doctor’s guidance, pay attention to appropriate exercise, strengthen the body’s immunity, and actively treat the primary disease if there is any other disease.