(Investigator 86, 2002 September)
A FATAL CONDITION
Kuru is a rare fatal condition occurring in the New Guinea Highlands and first observed in the early 20th century. The first symptom is an unsteady gait. Then – during about six months – it progresses to slurred speech, perpetual trembling, muscle jerks, outbursts of laughter, loss of balance and coordination, inability to stand or eat, and finally incontinence, difficulty in swallowing, ulcerations, coma and death.
THE DEMONISM/SORCERY HYPOTHESIS
ONE hypothesis was that KURU is a symptom of "demon possession" or a manifestation of sorcery. This is what indigenous people believed and some Christian missionaries accepted this. They observed that as Christianity spread and discouraged indigenous rituals, cases of Kuru declined.
The following is
1972 letter by a
sectarian missionary named Mike F. It advances the "demon" hypothesis:
ON "KURUKURU" — OR 'THE LAUGHING DEATH'
First some facts:
a) It in
found in the
Fore area of Okapa
Scientists from all over the world have come over the years trying to find a mysterious virus that affects only the genes of a person, since they have been unable to find any other causes of the 'disease'.
The huge medical station, Awande, was especially financed to cure the 'disease'. It has now been deserted after not being able to cure a single case. They would not accept demonism but attributed the 'disease' to cannibalism. It’s true that they are not the only ones STILL practicing cannibalism today but here is the difference; Normally, the cannibal eats only the muscle areas (to inherit their victims strength usually).
The people of the Fore/Okapa area eat their relatives only and at the point of death – so everything is still nice and warm! Then, instead of eating the meat, the women and children eat the viscera and brains. The men rarely participate at all and, should they do so, they prefer the meat. They believe the dead relative could live on in their bodies in this way.
The above theory remains a theory, and remains unproven.
What the natives think (know) it is:
They think it is the local medicine man up to no good. He is known locally as the Sangumma. 'He' could also be a 'she'. Both are equally as powerful and highly feared and respected. On realizing that one has contracted kurukuru (the first sign being not being able to stand on one leg) one would buy off the Sangumma man who in turn would repay the man who had put up the Sangumma to put the 'hex' on the victim. However, should three months elapse before the Sangumma is paid off then even the Sangumma cannot call off the 'hex'. In that case the victim will surely die.
The method the Sangumma uses to start the 'hex’ has echoes of voodooism in as much as they actually use the victim's nail-clippings, hair, etc. These are rolled up in special leaves and suspended rather tightly from each end and stretched from point A to point B in a swampy area. While the breeze blows the object in suspension then the 'hex' progresses until death occurs, or the string supporting the thing is broken so that it falls onto the ground where the wind cannot affect it – the 'hex' is broken.
But the breaking of the strings must be down within three months.
Anyone could break the 'hex', if they find it, but they are afraid of the swampy areas where the spirits lurk. Somehow the victims 'know’ when the 'hex' has been lifted.
Brother Ben C----- broke down one of those dreadful things once in his logging area there. The locals knew he must have done so since the latest victim began to recover…
SCIENTIFIC RESEARCH – GENES AND VIRUSES
The first to study Kuru scientifically was Dr. Vincent Zigas who arrived in New Guinea in 1955 and was alerted to Kuru’s existence by Patrol Officer MacArthur.
In 1957 Zigas interested Dr. D C Gajdusek who had come to research child development and disease patterns. In March a Research centre, constructed initially of native materials, was set up west of Okapa. Primitive at first, the research facilities improved during the next 10 years after which the place was closed down.
The first researchers into Kuru noticed it seemed to run in families. They therefore postulated a genetic disorder – a mutation passed to offpsring. This explanation lost credibility because Kuru was common yet always fatal. A lethal genetic disorder should decrease in incidence as victims die and the proportion of genes responsible for it decreases in the gene pool.
The next hypothesis was a slow-acting virus. In 1963 Dr. Gajdusec inoculated 8 chimps with brain extract of Kuru victims. 1½ to 2½ years later 7 of the chimps had Kuru-like symptoms. (New England J. of Medicine, 1967, pp. 276, 392) This suggested a slow virus.
However, a virus could not account for the sex-ratio of victims. In 1957 Kuru claimed over 200 lives of whom 30% were children under 15. The sex ratio of child victims was 1:1. Among adults, however, females outnumbered males 25 to 1.
What almost all victims had in common was having engaged in the ritual eating of the dead including eating previous victims of Kuru. Eating of the dead was done mainly by women and children. Therefore, if cannibalism transmitted Kuru, it seemed to explain why so few adult males had the disease.
Cannibalism was suppressed in New Guinea in the 1950s but continued in remote areas until the late 1960s. If the cannibalism hypothesis is correct then Kuru should decline from the 1960s onward – which it has done.
Regarding the hypothesis that cannibalism, including eating of brains of previous Kuru victims, accounts for transmission of Kuru Zigas concluded: "this hypothesis...should be advanced with much hesitation." (The Medical Journal of Australia, 1975, Sep. 20, p.485)
Subsequent research suggested that Kuru along with certain other degenerative diseases are both "infectious and inherited". (New Scientist, 1989, April 8 p. 28; Nature, Vol 338, p. 342)
In other words
susceptibleness to Kuru might
be transmitted via genes, but actual infection is by eating the brains
of previous Kuru sufferers.
THE PROBABLE ANSWER
Kuru is now considered a member of a class of diseases referred to as "transmissible spongiform encephalopathies" (TSEs) known also as prion disease. Other TSEs include Creutzfeldt-Jacob disease in humans, bovine spongiform encephalopathy (mad-cow’s disease) in cattle, scrapie in sheep and goats, and chronic wasting disease in deer.
Prion disease was identified by an American, Stanley B Prusiner, in 1982. Prions are infectious particles, composed of protein, which build up in the cells of the central nervous system and slowly kill them. This was a new theory in biology. Unlike viruses and bacteria prions lacked genetic material (DNA) yet could replicate without it. They replicated by converting normal protein they came into contact with into a different configuration. The process is a chain reaction that progressively damages the brain.
If Kuru is a
the symptoms are
due to chronic brain and central nervous system degeneration. And the
for the puzzling age and sex distribution of victims is:
TSEs, including Kuru, have a long incubation period – symptoms may take several decades to appear. Kuru effects the base of the brain responsible for coordination which accounts for the initial symptoms of unsteady gait, slurred speech and tremors.
that prions sometimes
also result from mutations in the human PrP gene that codes for PrPC
Cells then produce an altered version of this protein. This means that
DNA mutation accounts for some cases of "prion disease" possibly also
The "gene hypothesis" is therefore partly back.
For decades the cause of Kuru was unknown and debate is even now not finalised. This scientific doubt led some Westerners to accept the interpretation of sorcery. The observation that as Christianity spread Kuru declined is explained by the ban on cannibalism at the same time. Presumably missionaries also discouraged converts from eating dead relatives. The negative correlation – Christian increase/decline in Kuru – therefore seems accidental, not causative.
The recovery of a Kuru victim (see Mike F. letter above) when Kuru is always fatal can be explained by misdiagnosis. The initial signs of unsteady gait and inability to stand on one leg can have many causes besides Kuru!
something can't be
explained we should not immediately implicate the supernatural. To do
may be premature.
Cooke, J. (1998)
Cows & The CJD Catastrophe. Random House. Australia.
National Institute of Allergy and Infectious Diseases.
Prusiner, S.B. (1995) Prion diseases. Scientific American, Volume 272, No. 1, pp. 48-56.