The purpose of this study is to understand what causes a continuing fatigue for a long time with a number of symptoms occurring at the same time (Chronic Fatigue Syndrome-CFS). Epstein Barr Virus is among the group of viruses that have been associated with a continuing fatigue for a long time with a number of symptoms occurring at the same time, but the cause is still unknown.

Epstein-Barr virus (EBV) is the etiological agent for heterophile positive infectious mononucleosis (IM). It is also an oncogenic herpes virus associated with African Burkitt's lymphoma (BL),nasopharyngeal carcinoma (NPC) and AIDS-associated B-cell lymphomas. EBV is also among a group of viruses that have been associated with chronic fatigue syndrome (CFS), although the etiology of CFS still remains unknown.Findings may lead to hypothesize that EBV enzymes, such as the dUTPase, have the capacity to induce immune dysregulation of the T-cell and NK cell responses and that this immune dysregulation produces immunopathology that results in the symptoms that we call CFS.

Inclusion Criteria:

• Healthy adults for controls.
• Adults with chronic fatigue syndrome.

Exclusion Criteria:

• Individuals with significant medical illness in reference to immunosuppressant drug.

Note: We recruit participants in the Mississippi area who could come in our site to provide blood draw.

18 y/o and above with history of CFS matched those without as to age and gender.