It combines, since at least six months :
- a sensation of intense tiredness, of infectious kind, with at least 50 % reduction of daily activity;
- memory, concentration, and mood disorders, which can remind of a depressive or generalized anxiety chart
- functional disorders (locomotor, digestive, cardio-respiratory...) like "somatization" symptoms (hypocondria, hysteria...).
- Sleep disorders: insomnia, hypersleepiness