Seattle-King County Public Health is investigating an outbreak of E. coli O157:H7 that is potentially associated with four Evergreens restaurants in Seattle. 

The four restaurants are located in Seattle’s Pioneer Square, University District, the downtown area and in the International District.

Public health does not yet have conclusive results about what caused the outbreak and all four Evergreen restaurants have excellent inspection records.

Genetic testing on isolates from four of seven infected people indicates that the strains are the same, suggesting a common source.  The investigators are still awaiting test results on the other three patients.

Currently, available data indicates that this strain is different from the strain currently causing a national outbreak of E. coli associated with romaine lettuce grown in Salinas, CA, that the U.S. Centers for Disease Control and Prevention announced on Nov. 22.

Since Nov. 20, the Seattle public health officials have learned of six people who have tested positive for E. coli O157:H7 after consuming food from four different Evergreens restaurants in King County. One additional person had an E. coli O157:H7 infection with the same genetic fingerprint as the others but did not report consuming food at Evergreens. E. coli symptoms include bloody diarrhea, stomach cramps, and nausea.

Illness onsets occurred from Nov. 10-15. Meal dates were during Nov. 5-11.

One person was hospitalized. Everyone who reported illnesses has recovered.

Between Nov. 21–25, Environmental Health investigators visited the Evergreens locations where the ill people reported eating. During their field inspections, investigators did not observe environmental or behavioral risk factors associated with the spread or proliferation of E. coli, such as poor hand-washing or improper time and temperature control of foods.

Officials say this apparently local outbreak could be the result of a contaminated product delivered to and served at the Evergreens locations. In addition, many of the people who became ill after eating at Evergreens also reported eating raw vegetables, including leafy greens, from sources other than Evergreens in the days prior to their illnesses, meaning they could share a source for their illnesses that is unrelated to Evergreens.

Public Health investigators reviewed with staff at all four locations proper sanitizing practices to help prevent the spread of E. coli. In accordance with CDC’s recommendations, Evergreens restaurants discarded all romaine lettuce products from their stores, including romaine on the line and in coolers. Finally, management reviewed their sick policy with all employees.

As per agency protocol, Public Health investigators revisited the four Evergreens restaurant locations where ill cases reported eating to confirm that these actions were taken.

At this time, Public Health has not identified any employees who experienced similar symptoms before or after meal dates for the ill customers, but we are still surveying all employees. During their visits, investigators reviewed the requirement that restaurant employees are not allowed to work while having vomiting or diarrhea.

Public Health collected samples of various product samples from the four Evergreens locations where the ill people ate E. coli testing of these food products are pending.

Public Health is working with the Washington State Department of Agriculture and the United States Department of Agriculture on tracing back the distributors and sources for ingredients the ills consumed in their meals. Traceback is used to identify other points of contamination up the supply chain.

All seven of the people reporting illness tested positive for E. coli O157:H7. Of the four ill people for whom testing is complete, all four isolates tested shared the same E. coli genetic fingerprint, suggesting that they have a common source of infection.

E. coli bacteria normally live in the intestines of humans and animals. Many strains of E. coli bacteria exist, and most of them are harmless or beneficial to human health. STEC are strains of E. coli that produce Shiga toxin (such as E. coli O157: H7) and can cause serious illness in people.

Infection with STEC can occur through consumption of undercooked ground beef and other beef products; unpasteurized (raw) milk, cheese, and juice; contaminated raw fruits, vegetables, sprouts, and herbs; water contaminated with animal feces, or by direct contact with farm animals or their environment. Ready-to-eat foods can also be contaminated with STEC through contact with raw beef or raw beef juices in the kitchen.

Symptoms of STEC include diarrhea (which often becomes bloody) and stomach cramps, with mild or no fever. Illness typically lasts several days and people can spread the infection to others even after symptoms resolve.

  • STEC infections usually resolve in 5–7 days, but recovered individuals may still spread the bacteria. Up to one-third of children may continue to excrete STEC for as long as 3 weeks.
  • People sick with suspected STEC infection should not work in food handling, patient care, or childcare settings, and children sick with suspected STEC infection should not attend daycare until they have seen a healthcare provider and been tested for STEC infection, even if their illness is mild. People with a STECinfection who work in or attend these sensitive settings must be cleared by Public Health before returning. 

General advice for reducing the risk of contracting STEC:

  • Avoid eating high-risk foods, especially undercooked ground beef and other beef products, unpasteurized (raw) milk or juice or cheese, and raw sprouts.
  • Use a food thermometer to make sure that ground beef has reached a safe internal temperature of 160° F.
  • Wash hands before preparing food, after diapering infants, and after contact with cows, sheep, or goats, their food or treats, or their living environment.
  • Thoroughly wash fresh produce before eating.

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