Public Health investigated an outbreak of Shiga toxin-producing E. coli (STEC) associated with I Love Sushi and Café Mario at Nintendo of America campus in Redmond. Café Mario is operated by Sodexo and is not open to the public. I Love Sushi is a food establishment that operates out of Café Mario once a week.

This outbreak appears to be over. After a thorough investigation, we do not have enough evidence to connect I Love Sushi to this outbreak.. No single food item prepared by Café Mario has been identified as the source of the illnesses. Everyone who reported illness has recovered.


Since July 2, 2018, we have learned of 22 people in WA (20 in King County and 2 in Snohomish County) who developed symptoms consistent with an STEC illness, including diarrhea (bloody or non-bloody) and abdominal cramps. All 22 of these ill people are adults who work at the Nintendo of America campus in Redmond. Illness onsets occurred during June 11-July 5, 2018.

The 22 people who got sick all ate food from Café Mario on multiple days before becoming ill. Only four people who got sick also ate at I Love Sushi.

We learned of two additional people from King County who tested positive for E. coli infections with the same bacterial strain as the cases associated with Café Mario. However, these two people had no known connection to Café Mario or Nintendo, and we could not identify any other potential sources of exposure in common with any of the other people who got sick. We are not including these two people in the overall case count of this outbreak.

Public Health actions

On July 3, 2018, Environmental Health investigators visited Café Mario. Inspections were completed for both Café Mario and I Love Sushi.

At Café Mario, investigators identified possible risk factors for cross contamination and spread of bacteria, including improper hand washing practices and improper cold holding temperatures of food; corrective actions were addressed with Café Mario’s management. At I Love Sushi, possible risk factors were also identified and discussed, including improper temperature storage of foods. Both restaurants were not open on the July 4 holiday.

On July 5, 2018, investigators closed Café Mario and the onsite I Love Sushi food services. Investigators revisited both food establishments on July 11, 2018, and both were allowed to reopen the same day. Café Mario and I Love Sushi both completed a thorough cleaning and disinfection of their facilities before reopening, and any remaining processed ready-to-eat food products were discarded.

We did not identify any employees of either restaurant who had a recent diarrheal illness. Investigators also reviewed with management of both food establishments the Washington State Retail Food Code requirement that staff are not allowed to work while having vomiting or diarrhea.

Laboratory testing

Four of the 22 people who got sick tested positive for STEC O26 with the same genetic fingerprint, suggesting that they have a common source of infection. The remaining people who got sick were not tested for STEC, but their symptoms are suggestive of STEC.

Environmental swabs were collected from both I Love Sushi and Café Mario for laboratory testing and all came back negative for STEC at the Washington State Public Health Laboratory.