Volume 8: Variant CJD
2. History of CJD surveillance up to 1990
Introduction

2.1 This chapter describes the understanding of the epidemiology (the incidence, the distribution and the causes) of CJD in 1990, before the establishment of the CJD Surveillance Unit (CJDSU) in Edinburgh. Work in this area was prompted by action in the USA in the mid-1970s by the United States Department of Agriculture (USDA) to ban the use of meat from sheep and goats exposed to scrapie for human consumption. ¹ The ban arose from concerns about the similarities of scrapie to kuru and CJD and the recent transmission of scrapie to primates. Whilst it was felt in Britain that there was no evidence of an increased risk of CJD from exposure to sheep, the USDA action prompted calls for increased research into a disease of substantial economic importance as well as a potential disease of humans. Thus investigation of the causal agents of scrapie in sheep and CJD in man began at the Agricultural Research Council's (ARC) ² Institute for Research on Animal Diseases in the late 1970s. Work was also initiated by the Medical Research Council (MRC) following the reported person-to-person transmission of CJD following a surgical transplant procedure in 1974. ³

2.2 In 1986, when bovine spongiform encephalopathy (BSE) emerged, knowledge derived from this earlier work was already widely available to government and scientists alike. Consequently, concerns about the risk BSE might pose to human health prompted recommendations for further CJD surveillance by both the Southwood Working Party on Bovine Spongiform Encephalopathy (see vol. 4: The Southwood Working Party 1988-89) and the Tyrrell Consultative Committee on Research into Spongiform Encephalopathies (see vol. 11: Scientists after Southwood).