There are common colds and influenza. Colds with phlegm, cough and itchy throat without fever are mostly considered to be caused by the common cold. The common cold is caused by a viral infection, and starts more rapidly, mainly manifesting itself in sneezing, nasal congestion, watery nasal discharge, coughing, and itchy throat, etc. The symptoms are relatively mild, and do not cause a systemic inflammatory response. Symptoms are relatively mild and do not cause a systemic inflammatory response, so they usually do not manifest as fever, and only in severe cases do they have fever, mild chills and headache. On the other hand, influenza is an acute respiratory infectious disease caused by the influenza virus, with a rapid onset of symptoms, mainly characterized by high fever, headache, fatigue, and generalized muscle aches and pains. If the flu symptoms do not get better or worse, it is recommended to go to a regular hospital in time to get a clear diagnosis and standardized treatment under the guidance of the doctor, so as not to delay the condition and bring adverse effects to the body.