Tired. Exhausted. Worn down. There are times when we've all felt such fatigue, when we don't want to go back to work for a week or two, or wish we could have a month off to rest. But chronic fatigue syndrome differs from the more typical feelings of fatigue; it is a debilitating disorder that interferes with a person's ability to participate in the activities of daily life, sometimes for long periods of time. Even the simplest task can become a hurdle to overcome, and expending just a small amount of energy can put a person right back in bed.

Some of the symptoms of chronic fatigue syndrome are constant tiredness and feeling easily exhausted. There may also be recurring dull headaches; joint and muscle aches; a feeling of feverishness and chills without high fever; depression; difficulty in concentrating on tasks; and tender lymph glands. Of course, many of these symptoms also occur as part of other illnesses, making chronic fatigue syndrome difficult to diagnose and to categorize.


Although the syndrome has only recently been publicized, it isn't new, and it's probably not increasing in frequency. However, the name, chronic fatigue syndrome, is new. Researchers chose the name because they believe this illness is not a single disease, but results from a combination of several factors. In addition, the name accurately describes the characteristic problems of the disorder without second guessing the underlying causes. Every time someone has tried to pinpoint a cause in the past, they've been mistaken.

A textbook written in 1750 by an English physician Sir Richard Manningham, described symptoms of a disease he calls "febricula," or "little fever," which sound strikingly. similar to those of chronic fatigue syndrome. People in that era also referred to an illness called "the vapors," characterized by great fatigue.

As early as 1871, physicians began diagnosing exhaustion in soldiers following the stress of battle. This version of fatigue syndrome became known as "soldier's heart," or "the effort syndrome." During World War I some 60,000 of the British forces were diagnosed with the problem and 44,000 of these were retired from the military because they could no longer function in combat.

In 1934, an American physician, Alice Evans, suggested that chronic fatigue was caused by a bacterial infection transmitted through farm animals. She called the illness "chronic brucellosis." In that same year, there was an outbreak of a strange illness called "benign myalgic encephalitis," so named because it involved both impairment in brain function and muscle pain. During the 1970's people equated the fatigue syndrome with hypoglycemia, or low blood sugar. But, in fact, people with chronic fatigue syndrome do not typically have low blood sugar. Among other possible culprits people suspected might cause chronic fatigue were Candida, a yeast, and the Epstein Barr virus, a type of herpes virus that causes mononucleosis, or "the kissing disease." There is no clearcut evidence, however, that any of these are the primary cause of the syndrome.

Another possible, but still unproven, theory is that severe allergies can trigger chronic fatigue syndrome; some people who believe this theory would rather call the resulting disorder "total allergy syndrome."



Public Health Service

National Institutes of Health