
Chronic fatigue syndrome (CFS) is an emerging illness characterized by debilitating fatigue
(experienced as exhaustion and extremely poor stamina), neurological problems, and a variety of
flu-like symptoms. The illness is also known as chronic fatigue immune dysfunction syndrome
(CFIDS), and outside of the USA is usually known as myalgic encephalomyelitis (ME). In the past
the syndrome has been known as chronic Epstein-Barr virus (CEBV).
The core symptoms include excessive fatigue, general pain, mental fogginess, and often
gastro-intestinal problems. Many other symptoms will also be present, however they will typically
be different among different patients. These include: fatigue following stressful activities;
headaches; sore throat; sleep disorder; abnormal temperature; and others.
The degree of severity can differ widely among patients, and will also vary over time for the same
patient. Severity can vary between getting unusually fatigued following stressful events, to being
totally bedridden and completely disabled. The symptoms will tend to wax and wane over time.
This variation, in addition to the fact that the cause of the disease is not yet known, makes this
illness difficult to diagnose.