Cold and cough do not cause pulmonary nodules. Cold and cough are mainly due to the decrease of immunity caused by the triggering factors such as cold, rain, staying up late, alcoholism, etc., which cause pathogens such as viruses, bacteria, mycoplasma, chlamydia, rickettsia and other pathogens to invade the body, causing inflammatory reactions of congestion, edema and exudation of inflammatory substances from the mucous membrane of the upper respiratory tract. Pulmonary nodules are mainly pathological manifestations of both lungs detected by X-ray, CT or MRI, and are mainly suggestive of inflammation, inflammatory pseudotumors, non-inflammatory exudation from various causes, and occupying lung lesions, including benign and malignant tumors. Inflammation in cold and cough is confined to the upper respiratory tract; the lower respiratory tract, including the lungs, does not show inflammation or pulmonary nodules.