The November 2018 outbreak of E.coli O157:H7 infections linked to romaine lettuce caused 62 illnesses across 16 states. The FDA zeroed in on the Central Coast growing regions of northern and Central California as being responsible for the contamination. The outbreak was declared over on January 9 and yesterday FDA released the report, “Factors Potentially Contributing to the Contamination of Romaine Lettuce Implicated in the Fall 2018 Multi-State Outbreak of E.Coli O157:H7”, which provides an overview of the investigation.
The report states that a sediment sample coming from an on-farm water reservoir in Santa Maria (Santa Barbara County, California) tested positive for the outbreak strain of E. coli O157:H7. Although this particular farm was identified in several legs of the Fall 2018 traceback investigations that occurred in the United States and Canada, as well as being a possible supplier of romaine lettuce in the 2017 traceback investigations, the FDA said that the farm is not the single source of the outbreak, as there is “insufficient evidence”. The traceback suggests that the contaminated lettuce could have come from several farms, because not all tracebacks led to the farm on which the contaminated sediment was found.