SEATTLE — The King County Public Health Department is working to determine the source of an outbreak of E. coli potentially associated with four Evergreens Salad restaurants in Seattle. 

Health officials said this strain of E. coli currently appears to be different from the strain causing the national outbreak of E. coli connected to romaine lettuce grown in the Salinas region of California. 

Since Nov. 20, 2019, King County Health has learned of six people who have tested positive for E. coli after eating food at four different Evergreens Salad restaurants in King County. An additional person was diagnosed with E. coli and their infection is the same strain as the others, however, that person did not report eating at Evergreens. 

The restaurants are located at: 

  • Pioneer Square - 106 1st Ave S.
  • University District - 4609 Village Ter NE
  • Downtown - 823 3rd Ave.
  • International District - 504 5th Ave. S. 

All of those locations have an "Excellent" food safety inspection rating from the King County Health Department. 

Health officials said between Nov. 21-25, Environmental Health investigators visited the Evergreens locations where the patients reported eating and they did not find any risk factors associated with the spread of E. coli, such as poor hand washing or improperly handling foods. 

The Evergreens locations have also tossed all their romaine lettuce and extensively cleaned their cutlery and other items to cut down on any possible spread of the infection.

Evergreens released the following statement Tuesday evening, "Food safety is our top priority. We work every day using best practices so the food in our restaurants is safe and healthy. We have been in close contact with the health department and continue to cooperate fully to learn more about the source of the issue."

"People need to know if they ate at an Evergreens location and developed symptoms of E. coli, which can be diarrhea, which sometimes is bloody, nausea, abdominal cramping, that they should seek health care if their symptoms are ongoing," said King County Public Health officials. 

Officials said this local outbreak could be the result of a contaminated product that was delivered and served at Evergreens. They also said some of the people who became sick after eating at Evergreens also said they ate raw vegetables, including leafy greens, from sources other than Evergreens in the days prior to their illness. 

That means they could share a separate source for their illness, unrelated to Evergreens, officials said. 

The King County Health Department has finished genetic testing on four of the seven local cases and officials said they did not match the genetic fingerprint of the strain connected to the national outbreak. However, health officials are still waiting for genetic testing from the other three cases. 

King County health officials reported last week that one local man has been diagnosed with E. coli connected to romaine lettuce from the Salinas region.

However, again, officials do not suspect these new cases are connected to the national outbreak. 

Evergreens setup a customer care number for guests: 877-394-4146.

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