Study results consistent with earlier estimates of vCJD prion prevalence in Britain
8 October 2010
The Health Protection Agency (HPA) and a team from the IoN Department of Neurodegenerative Disease (

This study, published in the Journal of Pathology, involved
using immunohistochemistry to examine 9,160 anonymised tonsils for the
presence of abnormal prions and found one sample showing evidence of
prions associated with vCJD.
Study author Dr Jonathan Clewley,
an HPA expert on vCJD, said: "We have used a sensitive test and the
result is consistent with findings of earlier studies."
The
anonymised tonsils used in this study were obtained from earlier studies
- they had been removed from patients for clinical reasons and would
otherwise have been discarded. Tonsils are one of a number of body
tissues known to harbour abnormal prions in people who carry vCJD -
other tissues where these prions can be found include the appendix.
Lead author Professor Sebastian Brandner,
said: "Prevalence studies such as this are vitally important as they
enable us to estimate the prevalence of vCJD in the population. However,
it is important to understand that we do not know how good these tests
are at picking up infected individuals and so the results may be an
underestimate.
"They also give an indication as to the number of
cases to expect in the future and the potential impact for the health
service. Prion diseases can have long incubation periods, and an
understanding of prevalence can help researchers devise measures to
prevent further transmission of the disease."
There have been
220 clinically confirmed cases of vCJD worldwide, with the UK being most
affected with 173 people having developed the disease, as a result of
the epidemic of bovine spongiform encephalopathy in cattle in the 1980s.
Large scale vCJD prion prevalence studies are challenging at present as
there is no valid test available to screen for the vCJD prion in
blood.
read more>> Health Protection Agency | MRC Prion Unit | IoN Department of Neurodegenerative Disease
reference>>de Marco, M. F., Linehan, J., Gill, O. N., Clewley, J. P. and Brandner, S. , Large-scale immunohistochemical examination for lymphoreticular prion protein in tonsil specimens collected in Britain. The Journal of Pathology, n/a. doi: 10.1002/path.2767