Variant Creutzfeldt-Jakob Disease (vCJD) is the human form of the fatal brain-wasting disease found in cows called bovine spongiform encephalopathy (BSE) – better known as mad cow disease. So far there have only been 177 confirmed human cases in the United Kingdom, according to the study. Forty-nine more cases have been reported in 11 other countries, according to the World Health Organization.
Previous research suggested maybe 1 in 4,000 people living in Britain were carrying the protein that causes vCJD, says Dr. Sebastian Brandner, one of the study authors and head of the Division of Neuropathology at Queen Square, one of the largest academic neuropathology departments in the UK. But that estimate was made using a smaller sample, says Brandner.