Another interesting aspect to the E coli in spinach issue (which I hope can be brought out in the next article) is the relationship between the new, virulent form of E coli and the modern beef industry. The bestseller "The Omnivore's Dilemma" by Michael Pollan spells it out well.
Basically, a side effect of feedlot fattening of steer with corn (not cattle's natural diet of grass) is that cattle end up with indigestion, illnesses and an acidified digestive system during their time on the lot. A cow's rumen is naturally a pH neutral organ, and the bacteria in cattle originally evolved in a pH neutral environment. E coli in meat could not survive human stomach acid and posed no undue threat. To combat the problems caused by the unnatural feedlot diet, modern steer are now given massive quantities of antibiotics along with their corn diet. Is it a surprise that a new antibiotic-resistant and acid-tolerant E coli has evolved? No. What can we do? Feeding cattle a few days of grass before slaughter apparently rids them and their manure of 90% of the toxic E Coli, but feedlot operators think that is too cumbersome. The push is on to irradiate everything instead! So we will have lethal spinach and other problems until agribusiness is forced to address the issue head-on.