The main manifestations of lower respiratory tract infections are fever and chills, cough and sputum, chest pain, dyspnea, and in a few cases, gastrointestinal symptoms. The common causes of lower respiratory tract infections are bacterial infections, fungal infections, viral infections, chlamydial infections and so on. They mainly include diseases such as bronchitis, bronchitis, and pneumonia. The common symptoms are as follows;. 1. Chills and fever: the body temperature can reach over 39 degrees accompanied by chills. 2. Coughing and sputum: initially irritating dry cough, followed by mucous bloody sputum, white mucous sputum, or purulent sputum may appear. 3. Chest pain: mostly manifested as severe pinprick-like chest pain, which may be aggravated with coughing. 4. Dyspnea: In severe cases, the disease may lead to solid changes in the lungs, causing insufficient ventilation and dyspnea. 5. Other symptoms: some patients may experience gastrointestinal symptoms such as nausea and vomiting, diarrhea and so on. Reminder: If the above symptoms occur, it is recommended that treatment be carried out under the guidance of a professional doctor. During the period of illness, pay attention to rest, eat a light diet, do not eat cold and irritating food, Lower respiratory tract high fever should be timely consultation, under the guidance of the doctor for treatment, not self-medication, so as not to cause adverse reactions, delay treatment.