Such comments will be considered when determining whether to amend the current guidance. 9200 Corporate Blvd., Rockville, MD 20850. Comments may not be acted upon by the Agency until the document is next revised or updated. At this point in time the incubation period of BSE appears to be from 2 to 8 years. There is currently no treatment, nor is there a validated test to detect the disease in a live animal.
Diagnosis is determined by microscopic examination of brain tissue.
The nature of the BSE agent is widely theorized to be a prion, an abnormally folded version of a normal cellular protein. The abnormal protein then recruits additional molecules of normal protein and facilitates their conversion to the abnormal form. The agent is extremely resistant to traditional forms of disinfection and sterilization. As new information on the diagnosis, treatment and nature of the agent becomes available, this guidance will be modified as appropriate. Epidemiologic data suggest that the BSE epidemic in Great Britain which began in 1986 occurred through feeding cattle contaminated meat and bone meal as a protein source.