Possible Clues:

• There's no rip, oddly, in the infectious protein particle
• Protein particle believed to cause BSE
• Infectious agent believed to cause BSE
• Cause of BSE
• Petrel bird with saw-toothed bills
• Southern seabird
• Believed cause of BSE
• Finally trap unstable iron particle
• Cause of disease in jail Sweden avoided
• Monk prematurely finished by new cause of infection