WASHINGTON — The Centers for Disease Control and Prevention warned consumers, eateries and stores to get rid of all romaine lettuce, whether fresh heads or bagged salad, in the wake of another E. coli multistate lettuce outbreak.
Last spring, the outbreak that took five lives and resulted in stores and restaurants temporarily removing romaine from the menu was traced back to a small stretch of irrigation canal in the Yuma, Ariz., region.
But the Food and Drug Administration said Nov. 1 in its environmental assessment of the crisis that it remains a mystery to investigators how the irrigation canal was contaminated with the deadly bacteria or how that water contaminated the lettuce.
The Centers for Disease Control and Prevention declared the outbreak over by June 28; the last harvest from the Yuma region was April 16. By that time, two deaths from eating the lettuce had been reported in Minnesota, and there was one death each in Arkansas, California, and New York. Out of the 210 known infections reported in 36 states, 96 people were hospitalized and 27 developed a type of kidney failure. Illnesses connected to the same outbreak were also reported in several Canadian provinces.
The FDA report said investigators were “uncertain” as to how the E. coli “was introduced into this 3.5-mile stretch of irrigation canal water.” Though a concentrated animal feeding operation is located next to the canal, investigators “did not identify an obvious route for contamination of the irrigation canal from this facility” and samples collected at the facility did not match the outbreak strain.
“Other possible explanations for how the irrigation canal became contaminated are possible, but the [environmental assessment] team found no evidence in support of alternative explanations,” the report added.
As that still remains a mystery, the CDC said U.S. and Canadian health officials are investigating Shiga toxin-producing Escherichia coli O157:H7, a different strain than the Yuma outbreak, after 32 people were sickened in 11 states and 18 people fell ill in Quebec and Ontario. The illnesses began Oct. 8.
“The quick and aggressive steps we’re taking today are aimed at making sure we get ahead of this emerging outbreak, to reduce risk to consumers, and to help people protect themselves and their families from this foodborne illness outbreak. This is especially important ahead of the Thanksgiving holiday, when people will be sitting down for family meals,” said FDA Commissioner Scott Gottlieb. “We want to get this information out to consumers early. While we’ve made progress, it’s still early in this investigation and work remains to pinpoint the source of contamination that contributed to this outbreak and allow us to employ more targeted measures to reduce future risk.”
Gottlieb said there’s not enough traceback information “to request a recall from specific suppliers” so consumers “can avoid eating and discard any romaine lettuce.”
“Industry can also contribute greatly to containing and stopping this outbreak by voluntarily withdrawing any romaine products from the market and by withholding the distribution of romaine until we can ensure the outbreak is over or we can identify a specific source of contamination,” he added. “This isn’t the first romaine outbreak we have seen in the recent past, and we will continue to take steps to identify the root causes of these events and take action to prevent future outbreaks.”
The CDC advised that care should be taken to toss everything including romaine, including spring mix and Caesar salad kits. Refrigerator shelves and drawers that held romaine should be washed and sanitized.