Mild lung infections do not affect a patient’s life expectancy, while severe lung infections can significantly shorten a patient’s life expectancy, and there is no exact clinical timeframe for how long they can live. The impact of a lung infection on a patient’s life expectancy is related to the severity of the pneumonia, the patient’s age, physical status, and other factors, and there are large individual differences. If a pulmonary infection occurs in a young patient who was previously in good health, it will resolve in 7-14 days after regular anti-infective treatment and symptomatic supportive therapy, and will generally not affect the patient’s life expectancy. In contrast, in elderly patients with multiple diseases, lung infections can severely impair physical function and may involve multiple organs, which may greatly affect the patient’s life expectancy and even lead to death, even with standard treatment. Therefore, patients with pulmonary infections should be seen by a respiratory clinic in a timely manner, and regular treatment should be provided for different pathogenic bacteria to avoid serious consequences.