POSTED: 2:35 pm PDT October 26, 2006
UPDATED: 3:37 pm PDT October 26, 2006

WASHINGTON -- Wild pigs may have spread deadly bacteria onto a California spinach field, sparking an outbreak that killed three people and sickened more than 200 others nationwide, investigators said Thursday. They also said the outbreak appears to be over.

No one has become ill from eating contaminated spinach since Sept. 25. "All evidence points to this outbreak having concluded," said Dr. Kevin Reilly of the California Department of Health Services.

State and federal investigators have narrowed their focus to the ranch, where boar trampled fences that had hemmed in 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 outbreak, Reilly said.the spinach field less than a mile away, Reilly said. The pigs could have tracked the bacteria into the field or spread it through their droppings, he said.

Investigators also are looking at runoff, flooding, irrigation water, fertilizer and other wildlife, including deer, as possible sources.

Investigators first recovered the same strain of bacteria earlier this month from three cattle manure specimens collected on the ranch. On Thursday, Reilly said the strain had been isolated from six other samples collected on the ranch, including from cattle.

The finds mark the first time that investigators have identified a possible source for any of the multiple E. coli outbreaks linked to the heavily agricultural area. more at link: