The Institute for Environmental Health laboratory has isolated E. coli O157:H7 bacteria from deer feces on fields that grew contaminated strawberries implicated in a recent outbreak. E. coli infection is often spread by contamination with cattle feces, but in this outbreak wild deer seen in the strawberry field were the source.  Over 10% of 100 samples of soil and deer feces tested were positive for the pathogen, and further tests of the deer E. coli at IEH revealed that 6 of the 10 strains have a DNA "fingerprint" matching that of the human outbreak cases.

 In early August, Oregon Public Health officials identified fresh strawberries from an Oregon farm as the source of a cluster of Escherichia coli O157:H7 infections that sickened at least 15 people, including one person who died.  The implicated strawberries went on sale in July and the last of the berries were sold August 1, so the implicated strawberries are no longer on the market.  The strawberries were produced at the Jaquith Strawberry farm in Newberg, Oregon, but they were unlabeled at the time of sale because the farm sold its strawberries to buyers who then resold them at roadside stands, farmers’ markets and small grocery stores.  They were not available in major supermarkets and were only distributed in northwest Oregon.  A list of locations where the contaminated strawberries were sold during July is at http://www.oregon.gov/ODA/FSD/strawberries.shtml

The outbreak was recognized when several Oregon residents became infected with the same E. coli O157:H7 strain in early July, all of the isolates having a matching DNA “fingerprint”.  A total of 15 culture-confirmed cases with this outbreak strain occurred between July 10 and August 10.  Seven of the infected persons were hospitalized and two developed hemolytic uremic syndrome (HUS), including one elderly woman who died of kidney failure caused by her infection.

 Oregon health officials are concerned that consumers might have frozen the berries or made uncooked jam, so they are asking consumers to discard any fruit stand or farmer’s market strawberry products purchased in northwest Oregon in June and July.