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STEC O157:H7 — romaine lettuce (multi-state, 2024)

closed-recalled STEC E. coli O157:H7 (O157:H7) romaine lettuce Yuma, AZ

First reported: 2024-04-15 · Data as of: 2024-09-12

clear

Buyer guidance for romaine lettuce from Yuma, AZ

What to do

  • Romaine from Yuma growing region is now past the active outbreak period.
  • Standard food-safety practices apply: wash whole-head lettuce, avoid pre-cut bags if you are in a high-risk group.

What we don't know yet: Whether contaminated irrigation water sources have been remediated at implicated farms.

CDC MMWR ↗FDA EA ↗Peer-reviewed ↗

Summary

Multi-state outbreak of Shiga toxin-producing E. coli O157:H7 infections linked to romaine lettuce harvested from the Yuma, Arizona growing region. Hospitalization rate was high (46%) and 26 cases developed hemolytic uremic syndrome (HUS). FDA traceback investigation identified contaminated irrigation water from a nearby cattle operation as the likely source.

Traceback chain

FDA traceback investigation. Honest gap nodes indicate steps where the public investigation has not yet disclosed operator names.

farm Multiple Yuma-area farms Yuma County, AZ ◼ 6 batches
processor [redacted by FDA during investigation] Salinas, CA ◼ 1 batch
distributor Multiple national distributors national ◼ 1 batch
retailer Whole-head romaine sold at retail national ◼ 1 batch

Known gaps: specific farm names not released by FDA during active investigation

Cluster linkage

This outbreak is genetically linked to 1 other outbreak(s) via WGS/PFGE cluster:

Sources