- A new variant of Creutzfeldt-Jakob disease was discovered in 1996. This new variant was found to be related to encephalopathy. There are 5 known human transmissible spongiform encephalopathies, all created by prions. The prion, a pure protein, smaller than a virus is derived from a normal glycoprotein of human cells wall. The function of this protein is unknown but supposed to be connected with copper incorporation into superoxide dismutase. Creutzfeldt-Jakob disease is an early dementive disease with loss of neurons, accumulation of amyloid and spongiform degeneration of the brain. We discuss the epidemiology, diagnosis and therapy of Creutzfeldt-Jakob and its variant. The increased life expectancy will certainly cause these diseases to be more common, thereby having a definite affect on the economy in both developing and developed countries. Future therapy will concentrate on either preventing the creation of pathologic prions or extracting intracellular prions.