Infection is a common cause of fever, but other conditions can also bring the heat. Fever means a body temperature of 100.4° F (38°C) or higher. An infection, such as the flu, is the most common cause of fever.
Fever in Adults - Learn about the causes, symptoms, diagnosis & treatment from the MSD Manuals - Medical Consumer Version.
When does a fever in adults require medical attention? WebMD tells you what symptoms to look for and how to bring down a temperature.
A fever is a body temperature of 100.4 F or greater. Read about causes of fever in adults, symptoms, treatment, medications that may cause fevers, and different.