Previously, cattle manure had been the focus of the E. coli bacteria that contaminated a California spinach field, which expanded to kill three people and sickened more than 200 others nationwide. However, feral hogs also are on the radar screen.

State and federal investigators have now focused in on the ranch, where a wild boar trampled fences hemming a spinach field. Samples taken from a wild pig, as well as from stream water and cattle on the ranch, have tested positive for the same strain of E. coli implicated in the spinach outbreak, says Kevin Reilly, with the California Department of Health Services.

Still, investigators continue to look at three other ranches in the area. "We are not saying this is the source at this point," Reilly told the Associated Press. But feral pigs are one "real clear vehicle" that could explain how E. coli spread from cattle on the ranch to the spinach field less than a mile away, he said. The pigs could have tracked the bacteria into the field or spread it through their manure.

Source: Associated Press