Pneumonia may or may not lead to fever, because each patient’s physical condition is different, so the symptoms manifested after the emergence of pneumonia are also different. Most patients will have a fever after contracting pneumonia. Pneumonia is generally an infectious disease, and the invasion of pathogens such as bacteria, viruses, and fungi will stimulate the body and lead to a stress response, thus leading to fever symptoms. When a patient develops a fever from pneumonia, it is important to monitor the patient’s temperature at all times and seek medical attention. However, there are a small number of patients who do not develop a fever after contracting pneumonia. The condition may be mild, or the immune system may be so weak that the causative agent is unable to trigger an immune response or the immune response may be weak enough to cause a fever. Patients with pneumonia are advised to seek prompt medical attention to avoid delays.