Types of CJD

Types of Creutzfeldt-Jakob Disease (CJD)

There are four types of CJD with different symptoms and lengths of disease.^[3] The most common type of CJD, about 85% of cases, is Sporadic Creutzfeldt-Jakob Disease. The cause of sporadic CJD is unknown. Once symptoms appear, death occurs within a matter of months. Sporadic CJD typically affects people in their 60s.

Genetic or Familial Creutzfeldt-Jakob Disease occurs due to a genetic mutation.^[3] This form of the disease represents about 15% of all cases. Like sporadic CJD, genetic CJD affects people later in life. It lasts from 6 months to five or more years.^[3]

Acquired or Iatrogenic Creutzfeldt-Jakob Disease accounts for less than 1% of cases.^[3] Iatrogenic CJD is acquired from contamination during a medical procedure with tissues from persons with CJD.

CJD acquired from medical procedures progresses rapidly, and death usually occurs in 3-6 months.^[3]

Variant Creutzfeldt-Jakob Disease (vCJD), more commonly known as "mad cow disease," is a similar, but entirely different disease. Mad cow disease is a variant of CJD and is abbreviated vCJD. Mad cow disease usually occurs in people under 40 years old.^[4] vCJD progresses more slowly taking about 14 months for death to occur.^[3]