Mad Cow Disease May Be Minimal Threat in Britain
Analysis of tonsil specimens shows no evidence of subclinical variant Creutzfeldt-Jakob disease
FRIDAY, May 22 (HealthDay News) -- In the United Kingdom, the prevalence of the prion protein that causes variant Creutzfeldt-Jakob disease (PrPCJD) may be lower than previously estimated, according to a study published online May 21 in BMJ.
Jonathan P. Clewley, Ph.D., of the Health Protection Agency in London, and colleagues used two enzyme immunoassays to test more than 63,000 tonsils, including 12,753 tonsils from the 1961 to 1985 birth cohort, in which most disease-related prion protein cases have occurred, and 19,908 tonsils from the 1986 to 1995 birth cohort that also was exposed to meat contaminated with bovine spongiform encephalopathy.
The researchers found that no samples tested positive for PrPCJD. In the 1961 to 1985 birth cohort, they found that the confidence interval of 0 to 289 per million was lower than, but still consistent with, a previous study of appendix tissue showing a confidence interval of 60 to 853 per million.
"Continuing to archive and test tonsil specimens, especially in older birth cohorts, and other complementary large scale anonymous tissue surveys, particularly of post-mortem tissues, will further refine the calculated prevalence of PrPCJD," the authors conclude.