BOVINE SPONGIFORM ENCEPHALOPATHY CONTROL IN GREAT-BRITAIN

Bovine Spongiform Encephalopathy (BSE) is a new disease of cattle, first identified in November 1986. Although unrecognised at the time the first clinical case probably occurred in April 1985. The probable cause of BSE is the infectious agent which causes scrapie in sheep. Changes in rendering practices are believed to have increased the titre of scrapie agent in rendered meat and bone meal after 1981/82 to a level sufficient, when included in cattle feed, to cause clinical disease in cattle. Recycling of infection from rendered bovine material will also have occurred until the practice of feeding ruminant protein to ruminant animals in Great Britain was banned on 18 July 1988. Control measures are based on our understanding of the epidemiology of BSE, and fall into two broad groups: 1. Animal Health measures taken to prevent transmission of infection, so protecting other animal species and leading to the eventual eradication of BSE in cattle. 2. Public Health measures taken to protect consumers against the very remote risk that BSE, unlike scrapie, might prove to be transmissible to humans. The control measures include compulsory notification and restriction of movement of suspect cases, the isolation of any suspect which calves, the slaughter and destruction of the carcases of suspect cattle, the exclusion of specified bovine offal from unaffected cattle more than six months old from the food chain, and the ruminant protein feed ban referred to above which, in the absence of any other significant method of transmission, will eradicate BSE. The effectiveness of the control measures implemented in Great Britain from June 1988 onwards is now-demonstrable.