More retailers pulling lettuce from shelves over Cylcospora outbreak

 TONIGHT, WALMART IS THE LATEST BIG BUSINESS TO PULL ICEBERG LETTUCE LINKED TO A MULTI-STATE CYCLOSPORA OUTBREAK.     MORE THAN 67-HUNDRED PEOPLE HAVE BEEN SICKENED.     THE PARASITE HAS BEEN TRACED TO LETTUCE FROM CALIFORNIA-BASED TAYLOR FARMS -- AND USED BY TACO BELL.      CBS'S IAN LEE IN LOS ANGELES HAS MORE ON THE FALLOUT.