The cycle of viral colds is usually about a week, but the duration of the illness varies with the severity of the illness, clinical symptoms and the individual’s constitution. The duration of illness may be longer in patients with severe symptoms or complications. About 70%-80% of colds are caused by viruses and are mainly characterized by nasal symptoms such as sneezing, nasal congestion, runny nose, cough, dry throat, itchy throat, postnasal drip, thickened nasal discharge after 2-3 days, and may be accompanied by sore throat, headache, lacrimation, and breathlessness. In severe cases, there is fever, mild chill and headache. Physical examination may reveal congestion, edema and discharge from the nasal mucosa, and the throat may be mildly congested. Viral colds can also be easily complicated by pneumonia and myocarditis, which require vigilance and timely treatment.