Shiga toxin-producing E. coli O157:H7 infections associated with PCC Community Markets – West Seattle Co-op in Seattle

Highlights, updated April 23, 2024

Summary

Public Health investigated an outbreak of Shiga toxin-producing E. coli O157:H7 (also known as STEC). Three of the five people who got sick had testing that matched by whole genome sequencing or WGS (like genetic fingerprinting). This means they most likely got sick from the same source.

Based on information collected, we found one common source for all sick people which was a store-made guacamole purchased at PCC Community Markets – West Seattle Co-op on February 10, 2024. Even though we think this is the most likely source of illness, we do not know for certain. We did not find out how the guacamole might have been contaminated with STEC and did not have any left to test.

This outbreak appears to be over.

Illnesses

Since February 21, 2024, Public Health has learned about five people who got sick between February 14 – February 28, 2024. All five people had symptoms of STEC, including diarrhea (often bloody), stomach cramping, nausea, and vomiting. We have not found any employees sick with symptoms of STEC from PCC Community Markets – West Seattle Co-op.

Public Health actions

Disease Investigators conducted in-depth interviews with the five sick people to find common exposures and help prevent ongoing spread of STEC. Environmental Health Investigators visited the grocery on March 15, 2024. Investigators reviewed with establishment management the requirement that staff who have symptoms of vomiting and diarrhea are not allowed to work until they are symptom-free for at least 24 hours. Investigators provided education about preventing the spread of STEC — including proper handwashing, preventing bare hand contact with ready-to-eat foods, and preventing cross contamination between raw meat and ready-to-eat food during food preparation. When food workers have STEC, they need further testing before going back to work to make sure they are not contagious.

Environmental Health Investigators revisited the establishment on March 28th, 2024, and verified that proper compliance with cleaning, disinfection, and correct handwashing practices are in place.

Laboratory testing

Four people who became sick had testing that was positive for STEC O157:H7. Three people also had further testing showing they matched by whole genome sequencing or WGS (like genetic fingerprinting) at the Washington State Public Health Laboratory. One person who became sick did not have any testing done.