health

Classic CJD is the most common of the transmissible spongiform encephalopathies
(TSEs) found in humans. These diseases are called transmissible
because people (and animals) can get them through blood
transfusions, tissue transplantation, or eating infected food materials.
Spongiform means that the brain of a person or animal that has died
from a TSE has microscopic holes in it at autopsy and a generally
spongy texture when examined under a microscope. Encephalopathy
is the medical term for a disease of the brain that causes changes in the
function of the brain. CJD is named for the two German doctors who
first described it, Hans Gerhard Creutzfeldt (1885–1964) and Alfons
Maria Jakob (1884–1931).
CJD is related to several other rare prion diseases, including kuru, a
disease that was epidemic in Papua New Guinea in the mid-twentieth
century; and fatal familial insomnia (FFI), an inherited disease that has
been identified in only twenty-eight families around the world.
Other prion diseases infect animals; these include so-called mad cow
disease and scrapie, a disease found in sheep and goats. Some think that
mad cow disease is a form of scrapie and may have started in the early
1980s, when the remains of dead sheep were used as a protein supplement
in cattle feed. The importance of mad cow disease is its relationship
to variant CJD (sometimes called new variant CJD), the other major
human form of TSE. Variant CJD is thought to result from eating meat
from a cow infected with mad cow disease just as mad cow disease
resulted from feeding protein derived from infected sheep or cattle to
cattle. This type of feeding process is no longer used.