Fast-food giants have pulled fresh onions from their menus in the US after a McDonald's E.coli outbreak that killed one person and left 49 others sick.McDonald's, as well as its rivals including Burger King, KFC, Pizza Hut and Taco Bell, have all taken action, removing fresh onions from their menus in select US branches. The ingredient is believed to be the likely source of the outbreak that led to McDonald's removing the quarter pounder from one-fifth of its US restaurants.The onions are said to have come ...