Lung infections do not necessarily cause coughing. Lung infections refer to infectious inflammation that occurs in the lung tissue and are caused by a variety of pathogenic infections, such as bacterial infections, fungal infections, mycoplasma infections, and chlamydia infections, which can cause a variety of symptoms such as fever, cough, sputum, and chest pain. However, each patient’s constitution is different, and the type of pathogenic bacteria is different for each infection. The symptoms are not typical for every patient; some patients may have only cough symptoms, others may have only fever symptoms, and still others have no symptoms at all and are only detected during physical examination. Especially in the early stages of lung infection, the inflammation in the lungs has not yet involved the bronchi and therefore does not stimulate the cough receptors on the bronchi and thus does not produce cough symptoms.