Dear Doctors: It seems like there's a new E. coli outbreak every week. We never worried because we're careful about washing our produce, but our son-in-law got pretty sick with it after eating a fast-food hamburger. How dangerous is E. coli? Where does it come from? Is there any way to avoid it?
Dear Reader: E. coli is short for Escherichia coli. It's a large and diverse group of bacteria that make…