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The brain eaters:

A medical detective story behind our understanding of Mad Cow

Part 2: Trembling on the mountain

There had been only one report of a disease similar to vC-JD in young people. It was decades earlier and half a world away ≠ among the Fore tribesmen in the remote mountains of New Guinea. During the 1950πs, the Fore reported that sorcery was affecting increasing numbers of people. The victims were usually women, children, and teenagers, rather than adult men,. The tribe called this sorcery Kuru, or ≥shivering,≤ because that's what the victims did at first. But shivering progressed through loss of coordination and inability to walk, and ended in death.

A team of doctors and anthropologists evaluated the situation. They noticed that many victims seemed to be related to each other and to the deceased. Could this be a genetic disease that was inherited and passed from one generation to the next? As they investigated further, they discarded this hypothesis. Kuru seemed too common among the Fore, and too quickly fatal, to be inherited in a simple way (like sickle cell anemia or cystic fibrosis) without killing off the entire tribe in short order. (In less than 20 years, more than 1,100 members of this relatively small tribe died of the disease!)

From Deadly Feasts, by Richard Rhodes

Amazon ref:

http://www.amazon.com/exec/obidos/ASIN/0684844257/qid=1074893494/sr=2-1/ref=sr_2_1/002-1571195-4612027

So what caused Kuru? The original research team couldnπt figure that out. But they did determine how the disease was passed from one person to the next. The key seemed to be the Fore tribeπs unique way of mourning their dead. Instead of burying the body, women sliced it into pieces, combined it in bamboo tubes with salt, ginger and leafy vegetables, steamed it ≠ and ate it. They didnπt share this ritual meal with men, but only with other women and children. The brain, considered a special delicacy, was reserved for close relatives. As one woman who had participated in the ritual explained, ≥I will now always have part of my mother inside me.≤

The team proposed the radical hypothesis that whatever caused Kuru was transmitted through this ritual cannibalism. Because the people most often affected were women and children closely related to people who had died, the team further suspected that the infectious agent was concentrated in the brain and other nervous tissue.

One team member, Carleton Gajdusek, won the Nobel Prize in 1976 for confirming these hypotheses. Gadjusek conducted experiments in which he injected brain tissue from Kuru victims into chimpanzees. After long incubation periods, the chimps developed symptoms of Kuru. This experiment proved that Kuru could be transmitted from one individual to another through infected nervous tissue. Thus, once ≥whatever it was≤ killed one member of the tribe, the ritual meal or mourning spread it with gruesome efficiency through related women and children.

Amazon ref for Trembling Mountain:

http://www.amazon.com/exec/obidos/tg/detail/-/0738206148/qid=1074893405/sr=1-1/ref=sr_1_1/002-1571195-4612027?v=glance&s=books

But showing that Kuru could be transmitted did not lead immediately to an understanding of precisely what caused the condition. Gadjusek hypothesized that Kuru was caused by some kind of yet-unidentified virus that he couldn't isolate. He called it a ≥slow virus≤ because of the long period between infection and appearance of symptoms. (In humans, the incubation period for Kuru ranges from a minimum of around 2 years to as long as 25 years.) Gadjusekπs team later demonstrated, through a similar series of experiments, that C-JD itself could also be transmitted through nervous system tissue. But they still couldnπt identify the infectious agent that caused either Kuru or C-JD.

Rediscovering this information, British doctors were intrigued. The symptoms of Kuru, in retrospect, looked remarkably like vC-JD. But there couldn't possibly be any form of cannibalism going on in England ≠ could there? And where did the infectious agent originally come from anyway?

	Why did the Kuru research team first think that the cause of the disease might be genetic? Why did Gadjusek inject chimpanzees with brain tissue from Kuru victims? What did these experiments prove? What questions did they leave unanswered? Thought question: Sometimes you must wonder why biologists and doctors feel the need to give a name to conditions like this one. Can you see in this case why identifying and naming a medical condition could be useful and important?
Continue the Story Part 3: The prion connection: not a virus after all? Part 4: Where's the beef? Part 5: What we know now — and what don't we know
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