The answer to the central mystery in an ongoing national E. coli scare that has sickened at least 114 people was uncovered during a series of phone surveys conducted from Melissa Plantenga’s Lloyd Center office.

Plantenga, a research analyst who tracks food-borne diseases for the Oregon Department of Human Services, had telephoned the five E. coli victims in Oregon to answer a scattershot, 400-question survey.

One of her questions concerned bagged salad.

"I have had very few people ever say yes, they had eaten bagged greens," Plantenga said. "But the demographic of the victims being women and over the age of 20 suggested a produce item."

After logging four similar answers, she went online and researched a possible connection. A picture of the DNA pattern associated with patients she interviewed was sent to the CDC, where it was confirmed that it resembled a similar outbreak in Wisconsin.

With the new information, other states were then able to also pinpoint bagged spinach as the culprit in the E. coli outbreak. As a result, retailers as well as producers of the product pulled it from their shelves to prevent possible more contamination and illnesses.