A week before Thanksgiving, the Centers for Disease Control and Prevention announced it was investigating an outbreak of E.coli in romaine lettuce, the fourth such outbreak in two years. In early December, a fifth outbreak was discovered, this time linked to E.coli in packaged chopped salad. While Americans rushed to remove salad from their holiday tables, investigators from the Food and Drug Administration still have not determined where the bacteria came from, and why the same strain has repeatedly infected our lettuce supply.
E. coli are deadly bacteria that live in the guts of cows and some wild animals, such as birds and deer. They don’t harm the animals but can spread through the water, soil, and air to infect fresh vegetables. Lettuce growers have taken steps to protect their crops — implementing new rules to sanitize some irrigation water and increase the distance between their fields and large cattle feedlots. But what about the animal farms and feedlots where these bacteria often originate?
The April 2018 outbreak of Shiga toxin-producing E.coli, or STEC — the most common, deadly strain of the bacteria — was the largest outbreak in several decades…
