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Animal Disease and Human Health Risk
Animal Disease and Human Health Risk
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Transmitted From One Human to Another
Prion-related diseases have been found to be transmissible from one human to another.
This was discovered from studies of a formerly cannibalistic population in New Guinea
who honored their dead by using ritual cannibalistic rites. Children typically ate the
brains of their deceased parents during these rituals. Many of them contracted a
disease similar to CJD called "kuru" (which, in their native tongue, means shivering or
trembling).17 The disease sometimes took up to 30 years to develop. Young children
who engaged in these cannibalistic practices seemed to develop the illness sooner than
their older siblings or peers who also consumed infected brains.18
Other examples of human-to-human transmission of these devastating illnesses exist.
Before synthetic human growth hormone was available, individuals who were deficient
in this important compound often received it from pituitary glands removed from human
cadavers. There are reports of CJD being transmitted by this process. Other body
products from human cadavers have also been linked to CJD transmission. These include
eye (corneal) tissue and dura mater (a natural brain covering used during some brain
surgeries).19 Medical devices have transmitted CJD, including contaminated electrodes
that are used to measure brain waves in a special EEG test.20
One fascinating study emphasized the tenacity of these disease-bearing prions.21
Electrodes were used to probe the brain of a demented patient who turned out to have CJD.
The disease was inadvertently transmitted to two other patients when the same electrodes
were used on them. Following their last use in humans, over two years passed. During
that time the electrodes were cleaned three times and repeatedly sterilized with ethanol
and formaldehyde vapor. After this long interval, the electrodes were reimplanted in a
chimpanzee's brain. Within 18 months the chimp had come down with CJD. The authors
concluded: "This finding serves to re-emphasize the potential danger posed by reuse of
instruments contaminated with the agents of spongiform encephalopathies, even after
scrupulous attempts to clean them."
Ten Young Infected Britons
Awakened Public Health Officials
It was Creutzfeldt-Jakob statistics that really got the medical community's attention
in March 1996. By that time 10 young Britons and several farmers had become victims of
this devastating illness, as described in Figure 6: Britons Died of Creutzfeldt-Jacob Disease.
The fact that the disease affected a group of individuals whose average age at death was
less than 28 (and who were all younger than 42 when diagnosed) 22 was extremely unusual.
As we have already pointed out, CJD is typically a disease of older adults. Furthermore,
all 10 of these individuals had similar symptoms--but those symptoms were different from
those that usually accompanied CJD. For example, instead of causing death within 6 months,
this apparent CJD variant lingered for up to 23 months. The brain wave patterns of the
diseased individuals differed from the usual CJD patient, as did the type of mental
impairment they suffered as the disease progressed.23
These unusual disease features prompted a group of leading British scientists to raise the
concern that a new variant of CJD had emerged. They felt the most likely source of this
variant was BSE,24 meaning that this form of CJD was transmitted from the meat of cows
infected with BSE. Further thickening the plot was the occurrence of a worrisome cluster
of CJD-infected British dairy farmers. Four such farmers had died with CJD in the past
three years. Statisticians said that such a cluster would be very unlikely to occur
simply by chance.25
According to the microbiologist Dr. Jeffrey Almond, a researcher and spokesman (at the
Conference on Emerging Infections at Harvard University) for the British government's
BSE advisory committee, as of June 1997 there had been 19 confirmed cases of this new
CJD causing death, one of which occurred each in France and Italy.
References
17 Feinberg, M.B. Slow Virus And Retrovirus Infections. In: Scientific American Medicine (CD-ROM), 1995.
18 Dillner L. BSE linked to new variant of CJD in humans. BMJ 1996 Mar 30;312(7034):795.
19 Creutzfeldt-Jakob disease in patients who received a cadaveric dura mater graft--Spain,
1985-1992. MMWR Morb Mortal Wkly Rep 1993 Jul 23;42(28):560-563.
20 Creutzfeldt-Jakob disease in patients who received a cadaveric dura mater graft--Spain,
1985-1992. MMWR Morb Mortal Wkly Rep 1993 Jul 23;42(28):560-563.
21 Gibbs CJ Jr, Asher DM, et al. Transmission of Creutzfeldt-Jakob disease to a chimpanzee
by electrodes contaminated during neurosurgery. J Neurol Neurosurg Psychiatry
1994 Jun;57(6):757-758.
22 Will RG. (National Creutzfeldt-Jakob Disease Surveillance Unit, Western General Hospital),
Letter to British neurologists on March 21, 1996: (printed report downloaded from Microsoft
Network's BSE forum).
23 Sir Kenneth Calman, Chief Medical Officer of Britain, "A new variant of CJD" (a message to
British physicians); 3-22-96 (printed report downloaded from Microsoft Network's BSE forum).
24 The British The Spongiform Encephalopathy Advisory Committee. Report to Parliament on March
22, 1996 (printed report downloaded from Microsoft Network's BSE forum).
25 USDA: APHIS (Animal and Plant Health Inspection Service). Bovine Spongiform Encephalopathy:
Implications for the United States. A Follow Up. February 1996. Centers for Epidemiology and
Animal Health. Fort Collins, Colorado. p. 4.
Notice of Credit
The article above is compliments of the Uchee Pines Institute, Seale, Alabama, a teaching and
treatment facility devoted to natural remedies. For mor information, call 334-855-4781,e-mail:
ucheepine@csi.com, or visit their Website:
http://www.ucheepines.org.
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