The Associated Press points out that the FDA and CDC have investigated at least five produce-related outbreaks in the last four months, including the spinach E. coli outbreak, which sickened over 200 people and killed 4, and two Salmonella outbreaks that were traced to contaminated tomatoes served in restaurants. Combined, those outbreaks sickened 400.

The outbreaks cast media lights on the issue of food safety, and the focus grew more intense this month, when at least 71 customers at Taco Bell restaurants in New York, New Jersey, Pennsylvania and Delaware were reported ill.

Through a process of elimination, health officials have named iceberg lettuce as the culprit, and they feel confident about it despite a lack of scientific evidence.