11.   He believes that prion disease is caused by a virus.

12.   His laboratory at Case Western is the United States surveillance center for outbreaks of prion diseases.

13.   If the discoveries hold up, the researchers said, it may be possible to treat or halt prion diseases by blocking the action of the receptors.

14.   Meanwhile, the Centers for Disease Control and Prevention tracks prion diseases nationwide through death certificates, Belay said.

15.   Moreover, Prusiner and his colleagues say, prion diseases can be either inherited or acquired through infection.

16.   Moreover, studies of prion diseases are shedding light on how seeds of misfolded proteins can corrupt otherwise healthy proteins and propagate disease.

17.   Occasionally, genetic mutations lead to prion diseases that run in families.

18.   Prion diseases appear to be a category of infectious illness distinct from those caused by more common contagious organisms such as viruses or bacteria.

19.   Prion diseases can be inherited, occur spontaneously or be transmitted in other unknown ways.

20.   Prion diseases occur when a normal protein called a cellular prion misfolds into an abnormal shape that cannot be broken down by enzymes.