William Keene, senior epidemiologist with Oregon Public Health, told Lynne Terry of The Oregonian that 10 percent of the samples collected over the weekend from Jaquith Strawberry Farm tested positive for E. coli O157:H7.
Those samples included deer feces, which he initially suspected caused the outbreak. Now it seems certain they were the culprit.
"We’re increasingly confident that we will be able to prove beyond any reasonable doubt that deer were the source of contamination of the strawberries," Keene said.
"It could be there but in such low quantities that you have to collect thousands of samples," he said. "We don’t have the resources to pay for that kind of testing."
Now the lab has to confirm whether the specific strain of the bacteria in the samples matches the strain that sickened the 15 people. Two suffered kidney failure, including an elderly woman in Washington County who died. Two patients are still in the hospital.
That study, published in 1997, marked a big breakthrough. Until then the bacteria had been found in other animals, including horses, dogs and sheep, but scientists had always thought that cattle were responsible for poisoning food with E. coli O157:H7. Keene’s study showed that three samples of deer pellets out of 32 were positive for the bacteria.