In the sun-drenched fields of Yuma, Arizona, a deadly E.coli outbreak linked to romaine lettuce is casting a long shadow as the leafy greens growing season gets underway.
Together, California and Arizona produce about 95 percent of lettuce grown in the U.S. They divide the year seasonally. Each November, production shifts to Arizona which grows the bulk of our leafy greens until April. Last season, the U.S. Food and Drug Administration (FDA) identified Yuma as the origin of the deadliest multistate outbreaks in recent history.
The 36-state outbreak, which began in March 2018, sickened 210 people, almost half of whom were hospitalized. Twenty-seven people developed hemolytic uremic syndrome (HUS) a life-threatening form of kidney failure that affects about 10 percent of people with E. coli infections. Five people died. Not since 2006, when a similarly sized outbreak linked to spinach killed five people, has a leafy greens E. coli outbreak been so lethal.
Fred Pritzker, Founding Partner of the national food safety law firm Pritzker Hageman, said many of the people sickened in this outbreak reported eating romaine lettuce at a restaurant before they became ill. Some of them got sick weeks after health officials warned consumers not to eat and grocery stores and restaurants not to sell romaine lettuce grown in Yuma.
FDA, Growers Address Concerns
On November 1, FDA Commissioner Scott Gottlieb, M.D., 2018 released the agency’s environmental assessment of the outbreak investigation and a statement meant to calm concerns about the outbreak’s impact on this growing season. But it may have raised some in the process.
During the outbreak, the FDA was able to identify Yuma-grown romaine lettuce as the source, but it was never able to narrow it down. There were multiple processors, growers, shippers, and farms that supplied the lettuce associated with this outbreak to restaurants and retailers, the agency said. Then the FDA found the outbreak strain of E. coli in irrigation canals, but it wasn’t able to determine how it got there.
In early August, about a month after the Centers for Disease Control and Prevention (CDC) declared the outbreak over, the FDA released an update saying a concentrated animal feeding operation (CAFO) near the growing region may have been the source of the contamination of the irrigation canals. But, the environmental assessment released yesterday reveals that samples collected from the CAFO did not test positive for the outbreak strain. In fact, the report states, “the outbreak strain was not found in any of the other samples collected in the region. How the water contaminated the lettuce is uncertain.”
The agency also enumerated some of the difficulties it faced in tracing back the source of an outbreak linked to a highly perishable commodity. For one, the finished romaine product contained romaine from various farms. Second, the majority of the records were on paper or handwritten.
Going forward, the FDA will try to use new technologies to reduce the amount of time it needs to conduct a traceback investigation and plans to conduct testing on romaine lettuce samples.
The Arizona Leafy Greens Marketing Association said in a statement that its outbreak response includes “more rigorous risk assessments stemming from intense weather conditions and additional measures for the production of leafy greens near concentrated animal feeding operations; more prescriptive requirements for the cleaning and sanitizing of harvest equipment; and stronger traceback requirements.”