The infection hides in the intestine and lymph nodes and can survive in manure and pond water for a year or more, making transmission of the disease difficult to stop.
The biomass power station would burn rubbish, animal manure, woodchips, seaweed, corn stalks and other wastes, to heat water to create steam to turn turbines to produce around 300 megawatts of electricity.
Experts have come up with all sorts of hypothetical ways the E. coli could have gotten into the spinach, from manure that wasn't properly composted to runoff from cattle farms to contaminated irrigation water.