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Mononucleosis and Chronic Fatigue Syndrome


Chronic fatigue syndrome (CFS) is a poorly understood condition that develops mainly in adults ages 20 to 40. Its main symptoms include:

  • Persistent fatigue that interferes with daily activities and lasts longer than 6 months.
  • Mild fever.
  • Sore throat.
  • Swollen lymph nodes (sometimes called swollen glands).
  • Difficulty concentrating and short-term memory loss.
  • Sleep disturbance.
  • Irritability.
  • A noticeable decrease in physical activity.

In the past it was believed that chronic fatigue syndrome was caused by long-term infection with the Epstein-Barr virus (EBV). But research has shown that chronic fatigue syndrome and EBV infection are two different illnesses and that EBV does not cause chronic fatigue syndrome.

For more information, see the topic Chronic Fatigue Syndrome.


By Healthwise Staff
Primary Medical Reviewer E. Gregory Thompson, MD - Internal Medicine
Specialist Medical Reviewer W. David Colby IV, MSc, MD, FRCPC - Infectious Disease
Last Revised July 28, 2011

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