Creutzfeldt-Jakob Disease (CJD) is a brain disorder that usually occurs in people over the age of 60. It is sometimes called a “spongiform” disease because the brain may develop holes in it like a sponge. There are four types of CJD: sporadic, variant, familial and iatrogenic. Sporadic CJD occurs spontaneously and is the most common type of CJD in the United States. Variant CJD is associated with eating beef in the United Kingdom during the “mad cow” epidemic. Familial CJD is inherited through a genetic mutation. Iatrogenic CJD is transmitted by contaminated surgical instruments in high risk surgeries involving transplants of brain and spinal cord tissue. Every year about one person out of every million is diagnosed with CJD, primarily sporadic. There is no known treatment; most people die within 3 to 12 months of onset of symptoms.  At first, CJD can seem a lot like other diseases of the elderly. Symptoms include behavioral changes, confusion, difficulty remembering recent events, and loss of feeling in the arms, legs, or face. Patients may lose their balance or seem uncoordinated; they may have difficulty walking or have muscle jerks and spasms. A brain wave test (EEG) is often helpful in the diagnosis. Other special testing includes cerebrospinal fluid 14–3–3 protein and blood tests for genetic mutation. To be sure the person has died of CJD an autopsy must be done.  It is not known how most people get this rare disease, although we do know you do not get it from being around someone with CJD. Approximately 10–15 percent of cases are inherited (familial CJD) and a few cases have been related to transplants of tissues from the nervous system (iatrogenic CJD). In 1995, the first case of variant CJD was recognized in the United Kingdom and has been linked to ingestion of foods from cattle infected with “mad cow disease.”  


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Creutzfeldt-Jakob disease (CJD) is an extremely rare degenerative brain disorder (i.e., spongiform encephalopathy) characterized by sudden development of rapidly progressive neurological and neuromuscular symptoms. With symptom onset, affected individuals may develop confusion, depression, behavioral changes, impaired vision, and/or impaired coordination. As the disease progresses, there may be rapidly progressive deterioration of cognitive processes and memory (dementia), resulting in confusion and disorientation, impairment of memory control, personality disintegration, agitation, restlessness, and other symptoms and findings. Affected individuals also develop neuromuscular abnormalities such as muscle weakness and loss of muscle mass (wasting); irregular, rapid, shock-likemuscle spasms (myoclonus); and/or relatively slow, involuntary, continual writhing movements (athetosis), particularly of the arms and legs. Later stages of the disease may include further loss of physical and intellectual functions, a state of unconsciousness (coma), and increased susceptibility to repeated infections of the respiratory tract (e.g., pneumonia). In many affected individuals, life-threatening complications may develop less than a year after the disorder becomes apparent.

In approximately 90 percent of cases, CJD appears to occur randomly for no apparent reason (sporadically). About 10 percent of affected individuals may have a hereditary predisposition for the disorder. Reports in the medical literature suggest that familial cases of CJD are consistent with an autosomal dominant mode of inheritance. In addition, in some extremely rare cases, CJD may take an infectious form. The disorder is thought to result from changes (mutations) in the gene that regulates the production of the human prion protein or direct contamination (transmission) with abnormal prion protein in infected brain tissue.