Not Reassuring

From one of my professors:

'There was an American student when I was in Nairobi last Fall – I can’t remember her name – but she ended up in the emergency room with amoebic dysentery. The Drs. quizzed her on what she had eaten the last several days and decided it was lettuce. She said that she had bought it in a supermarket, sealed in plastic with “triple washed” printed on the outside of the package.'