With absolute certainty, another E. coli outbreak will explode, a visiting lecturer said Thursday.

John Besser, a clinical laboratory manager for the Minnesota Department of Health, was recently the guest lecturer a the University of Iowa. The MDH investigated an E. coli outbreak that had been traced to lettuce served at Taco John’s restaurants in Austin and Albert Lea, Minnesota, as well as in Cedar Falls, Iowa.

Though a recent outbreak was traced back to spinach grown in California, E. coli is not limited to the leafy plant. It is becoming prominent in a number of substances, said Besser. Last fall, an E. coli outbreak ripped across the United States, killing three and causing 31 cases of hemolytic uremic syndrome, which shuts down the kidneys.

Since there has been an increase in E. coli outbreaks traced to leafy greens and other produce, experts are predicting future outbreaks. Consumer advocacy groups have stepped into the debate over what can better be done to protect the public from E. coli and other harmful pathogens.  The Consumer Reports blog posted the Consumers Union opinion about California produce growers’ intent to publish marketing guidelines for crops:

Costco now requires suppliers to random test spinach at the processing plant, including for E. coli 0157:H7 and salmonella, another bacteria that can cause serious infections in some people. Within weeks, Costco expects similar testing for other bagged and ready-to-eat products, such as lettuce salads and baby carrots.

Shortly after the spinach outbreak, Natural Selection Foods, which processed the implicated spinach, started random testing of raw product for E. coli and salmonella. This month, it started testing finished product, too.

The United Fresh Produce Association has asked for federal oversight of the produce industry. Now, the FDA regulates processing plants but only gives growers guidelines.