E. coli is in poop, with this nastier strain being in unique poop. Poop is used as fertilizer. It's killed by cooking, but can re-contaminate ("cross-contamination") cooked foods by sucky food handling practices. Most people don't cook bean sprouts used in salads, therefore, there's a much greater chance of getting sick from eating sprouts.

Despite them saying sprouts were the culprit, contaminated fertilizer may have been used on other foods.

If you're eating in a place with iffy sanitation & food safety practices, peel, cook, or don't eat the food.