Reply #21: Actually, [View All]

[FourScore]

http://healthyamericans.org/topics/index.php?TopicID=24

Mad cow disease has an incubation period from two to eight years in cattle. The incubation period for vCJD in humans is unknown. It is likely that the incubation period ultimately will be measured in terms of many years or decades. The relatively long incubation period of mad cow disease in cattle increases the difficulty of monitoring and preventing transmission to other cows.


AND

http://pathmicro.med.sc.edu/mhunt/slow-vir.htm

New variant CJD disease (human BSE); nvCJD, vCJD

A form of CJD has been reported, predominantly in the United Kingdom, in patients who are usually younger (frequently under 40; average age at death: 28 years) than is the case for most CJD patients (average age of death: 68 years) (figure 8A). This disease is also different from the usual CJD in that patients tend to present with psychiatric problems and in that the course of the disease tends to be more protracted. Sufferers may eventually show any or all of the symptoms described above for other human prion diseases. The disease was first seen in 1996 and there is strong evidence to suggest that it is associated with exposure to BSE-contaminated beef. Strong BSE control measures have now been implemented. Autopsy reveals a distinctive neuropathological appearance and more PrP (prion protein) amyloid plaque (figure 7 and 9) type deposits than in typical CJD cases.

As of August 2006, 162 people have been reported with vCJD in the UK (figure 8b), 20 in France, 4 in Ireland, 2 in the United States and 1 each in Canada, Japan, Portugal, Spain and the Netherlands (the people from Canada, Japan and the US were probably exposed while living in the UK).

We do not know if we are seeing the beginning of a major outbreak or whether these will be the majority of cases of this disease ever seen. There is also concern because there appears to be more infectious agent in the peripheral tissues, especially the lymphoreticular tissue of patients with vCJD than with normal CJD. This raises questions about sterilization of surgical instruments etc. and the possibility of iatrogenic spread. This is also one of the reasons that the United States is concerned and conservative about protecting the blood supply (by screening out those who have spent considerable time in the UK or Europe). There is a possibility that vCJD agents may have been transmitted by blood transfusion in two cases in two British cases. In both cases the blood had not been leuko-depleted; it is thought leuko-depletion might decrease the chances of transmission by blood transfusion.