A condition resulting in massive, debilitating fatigue accompanied by diverse symptoms including memory loss, diminished powers of concentration, sleep disorder, headache, low-grade fever, muscle and joint pains, sore throat, tender lymph nodes, and a postexertional malaise lasting more than 24 hours. This condition is also known as postviral fatigue, chronic fatigue syndrome, and myalgic encephalomyelitis. It is often associated with stress.