SC Chronic Fatigue Syndrome Chronic Fatigue Syndrome Chapter 24. Until about 1983, doctors knew next to nothing about chronic fatigue syndrome. Its exact cause is still unknown. Some researchers used to think it was caused by the Epstein-Barr virus. Others suggest its cause could be a virus that has not yet been found.
Most experts now lean toward a theory of multiple causes.
Confusion, difficulty thinking, inability to concentrate These symptoms can signal a number of health conditions. As yet, no specific laboratory tests can diagnose the syndrome. For some, the symptoms are so debilitating that a normal working life is impossible. Yet others experience only a vague sense of feeling ill. In some cases, symptoms never let up, while in others they come and go.