Transmissible Spongiform Encephalopathies

Transmissible spongiform encephalopathies, or TSE's, are a family of central nervous system diseases that afflict different species of mammals. The common element among them is that they leave the brains of their victims with lesions that make them look like sponges when viewed under a microscope after death. Although the diseases may have slightly different symptoms and may be transmitted differently, all affect their victims' coordination and movement, and all are fatal.

TSE's that science has identified in animals include:

• Bovine spongiform encephalopathy in cattle
• Scrapie in sheet and goats
• Feline spongiform encephalopathy in cats
• Chronic wasting disease in deer and elk

TSE's in humans include:

• Classic Creutzfeldt-Jakob disease
• New-variant Creutzfeldt-Jakob disease
• Kuru
• Gerstmann-Straussler-Scheinker syndrome
• Fatal familial insomnia