GDC Terminology Comorbidity Risk Factor GDC Value Terminology SeroNet Authorized Values SeroNet Study Descriptors ACC/AHA Cardiovascular and Noncardiovascular Complications of COVID-19 Terminology Appendix 4: COVID-19 Cardiovascular Complications Terminology Postacute Cardiovascular Sequelae of SARS-CoV-2 Infection or Long-Term Cardiovascular Complications of COVID-19 Terminology ACC/AHA COVID-19 Appendix Authorized Values Chronic Fatigue Syndrome chronic fatigue syndrome C3037 SeroNet Chronic Fatigue Syndrome ACC/AHA A condition lasting for more than 6 months in which a person feels tired most of the time and may have trouble concentrating and carrying out daily activities. Other symptoms include sore throat, fever, muscle weakness, headache, and joint pain. A syndrome of unknown etiology. Chronic fatigue syndrome (CFS) is a clinical diagnosis characterized by an unexplained persistent or relapsing chronic fatigue that is of at least six months' duration, is not the result of ongoing exertion, is not substantially alleviated by rest, and results in substantial reduction of previous levels of occupational, educational, social, or personal activities. Common concurrent symptoms of at least six months duration include impairment of memory or concentration, diffuse pain, sore throat, tender lymph nodes, headaches of a new type, pattern, or severity, and nonrestorative sleep. The etiology of CFS may be viral or immunologic. Neurasthenia and fibromyalgia may represent related disorders. Also known as myalgic encephalomyelitis. Disease or Syndrome GDC Myalgic Encephalomyelitis Myalgic encephalomyelitis/chronic fatigue syndrome C0015674 Chronic Fatigue Syndrome Chronic_Fatigue_Syndrome Chronic Fatigue Syndrome Immunodeficiency Syndrome