Fever is a symptom of defence of our body, warning us that there is a problem and that it is on alert, in order to deal with the problem and protect us. The most important factor that must be investigated, is the cause of the fever. Fever recedes when we treat its cause, i.e. the disease causing it. Fever can become dangerous for our body when it exceeds 41°C. Depending on the cause of the fever and the medical history of the patient, the danger limits vary.