A body temperature above the normal 36.5°C that lasts for a long time is known as a fever. In most cases, if not always, it is caused by an infection (influenza, chickenpox, measles, meningitis and local infections (abscesses)).
Low fevers are not dangerous, but temperatures above 39°C can be critical and cause seizures in infants and young children.
Signs and symptoms of high fever
In the early stages you may experience:
• pallor;
• chills, in which the body trembles and teeth chatter.
If the fever intensifies, you may experience:
• skin redness and sweat;
• headache;
• weakness;
• pain throughout the body;
• increased heart rate and breathing;
• convulsions;
• comma.