Two weeks ago as the public was told that canal water was the likely source of the E. coli O157: H7 that caused the national outbreak involving romaine lettuce, growers in the region were told what they could immediately to do about it.

In a June 29 memo, the Yuma Safe Produce Council shared food safety recommendations with regional growers.  The Council said the practices it recommended should be “implemented at the earliest possible opportunity.”   The changes suggested included:

  • If overhead irrigation is used for crop production, the water should be treated to reduce the bacterial presence.
  • Irrigation water “in the reach “ that’s tested positive for E. coli O157: H7 should not be used for “foliar applications” unless treated to reduce the risk of bacterial presence.
  • Irrigation water “in the reach” that’s tested positive for E. coli O157: H7 should not be used for dust abatement unless the water is treated.
  • The same recommendations should be followed for water takeouts upstream and downstream of the affected areas.

“As food safety professionals, we believe the current CDC sampling results warrant an immediate response to the risk that has been identified,” the Produce Council members wrote growers in the Yuma region.

About 200 people were sickened in the recently ended E. coli outbreak.   The outbreak, which began last spring, resealed in five deaths.

Just two weeks ago, the federal Centers for Disease Control and Prevention (CDC) found the outbreak strain in canal water in the Yuma region.   According to the Produce Council, the U.S. Food and Drug Administration (FDA) and state and local regulatory officials traced the bad romaine to “many farms in the Yuma growing region.”

Water, soil and manure samples were collected in the region from June 4 to June 8, 2018.  “Evaluation of these samples is ongoing and any new matches to the outbreak strain will be communicated publicly and with industry in the region,” the Produce Council summary said.

“To date, CDC analysis of samples taken from canal water in the region has identified the presence of E. coli O157: H7  with the same genetic fingerprint a the outbreak strain” it added.  “We have identified additional strains of Shiga-toxin producing E. coli in water and in soil samples, but at this time, the samples from the canal water are the only matches to the outbreak strain.”

The summary says identification of the outbreak strain in the environment should help the additional investigation into the how the outbreak strain could have gotten into the water. 

Those involved in the investigation, including CDC, FDA, and state public health and regulatory officials, declared the outbreak over on June 28.   The investigation found the multistate outbreak of E. coli O157: H7 involved:

  • 210 people infected with the outbreak strain were reported from 36 states.
  • 96 people were hospitalized, including 27 people who developed a type of kidney failure called hemolytic uremic syndrome or HUS.
  • 5 deaths were reported from Arkansas, California, Minnesota (2), and New York.
  • Epidemiologic, laboratory, and traceback evidence indicated that romaine lettuce from the Yuma growing region was the likely source of this outbreak.
  • CDC laboratory testing identified the outbreak strain of E. coli O157: H7 in canal water samples taken from the Yuma growing region.
  • FDA is continuing to investigate the outbreak to learn more about how the E. coli bacteria could have entered the water and ways this water could have contaminated romaine lettuce.
  • According to the FDA, the last shipments of romaine lettuce from the Yuma growing region were harvested on April 16, 2018, and the harvest season has ended. Contaminated lettuce that made people sick in this outbreak should no longer be available.

It was the second E. coli O157: H7 outbreak of 2018 involving leafy greens