Bronchitis is not contagious. Bronchitis refers to chronic non-specific inflammation of the trachea, bronchial mucosa, and its surrounding tissues, mainly due to recurrent viral and bacterial infections, with the following clinical manifestations: First, acute bronchitis initially manifests as symptoms of upper respiratory tract infection, such as nasal congestion, runny nose, sore throat, hoarseness, low fever, peripheral weakness, accompanied by an irritating cough and pain behind the sternum, and coughing sputum. Secondly, chronic bronchitis, repeated coughing and gradually aggravated, coughing white sticky foamy sputum, more in the morning and not easy to cough up, sputum volume increases, thickens and turns yellow after infection. Third, shortness of breath and wheezing in the throat when breathing. Fourth, repeated infections, at this time to check the routine blood white blood cell count increased, repeated respiratory infections easily, so that the elderly patients deteriorate. So bronchitis is not an infectious disease, if suffering from bronchitis pay attention to keep warm, avoid getting cold, fresh and moist indoor air.