REDWOOD CITY -- The October outbreak of E. coli that caused the deaths of two elderly women and sickened dozens of other residents and staff of the Sequoias Portola Valley retirement home has been traced to prepackaged spinach, County health officials said Tuesday.
The prewashed, raw spinach was served during the first week of October, and sickened at least 16 people, a report by the Health Department's Disease Control and Prevention Unit said.
The federal Food and Drug Administration is in the process of tracing the spinach back to its grower and vendors, the report said.
As of Tuesday, the brand of spinach had not been determined, said Dr. Scott Morrow, a County health officer who helped conduct the investigation into the outbreak.
The home's kitchen is run by Sodexho USA, a multinational food service and distribution company that serves more than a million meals a day.
Sodexho provides kitchen staff, equipment and food to institutions like schools, jails and hospitals.
"We're pleased the investigation revealed that it was not a result of any problems with our food handling at the facility," said Leslie Aun, a Sodexho spokesperson.
County health inspectors have said the facility's kitchen could "serve as a model" for cleanliness, and an Oct. 15 follow-up investigation found only a minor infraction: one refrigerator was running at a temperature higher than 41 degrees.
The report found that the spinach, which was prewashed, was not washed again by kitchen staff.
Epidemiologists conducted dozens of interviews with residents and staff, inspected the kitchen several times and analyzed stool samples from the 16 confirmed E. coli sufferers before they narrowed the culprit down to spinach.
E. coli is a food-borne virus that causes severe abdominal pain, diarrhea and other symptoms. It is seldom fatal, but children and the elderly are more likely to die from the virus.
Eighty-five-year-old Alice McWalter, a professional choir singer, died in late October when E. coli caused kidney failure and abnormal blood clotting.
Another resident of the 315-bed home, 95-year-old Mildred Gonzalez, died after being treated at Stanford Medical Center, released back to the home and readmitted to the hospital.
Fourteen others were hospitalized.
Bill Marler, a Seattle-based lawyer who has collected tens of millions of dollars in settlements in food-poisoning cases, told The Times in October he had been contacted by several San Mateo County families, who reportedly want to file lawsuits.
Marler won a $15.6 million settlement from Jack-in-the-Box, and $12.5 million from Odwalla in cases going back several years.