Fever is the elevation of body temperature in a warm-blooded creature due to deregulation of the central "thermostat". It is generally a defence reaction to an internal aggression (such as an infection) leading to the activation of some mechanisms of immunity and inflammation. |n humans, the normal body temperature is 37° C (between 36 and 37.2, depending on the person).
In humans, flue is expressed by a group of nonspecific signs combining fever, headache, cough, pharyngitis, myalgia, asthenia and anorexia. Transmission of the disease from one person to another is essentially respiratory via droplets rich in virus produced by the coughing and sneezing of infected persons.