<<But isn't there a danger in eating off-the-shelf beef?>>

E. coli 0157: H7 food borne illness.  Those with underdeveloped and
compromised immune systems are most at risk.  The enterotoxin this bacteria
produces can cause hemolytic uremic syndrome (kidney failure).  Try telling
your child hooked up a dialysis machine for the rest of their lives that
eating raw beef makes them healthy.

Rob