Herman was retired on September 10, 2026. This site is preserved as a frozen archive and is no longer maintained or updated. Read the retrospective →

← All outbreaks

STEC O157:H7 — multi-matrix (Chipotle Mexican Grill, 2015)

closed-recalled STEC E. coli O157:H7 (O157:H7) multi-matrix (likely produce) multiple

First reported: 2015-10-19 · Data as of: 2016-02-29

clear

Buyer guidance for multi-matrix (likely produce) from multiple

What to do

  • Outbreak closed in February 2016.
  • Standard food-safety practices apply.

What we don't know yet: The specific ingredient(s) responsible for both outbreak strains remains undisclosed in the public FDA EA.

CDC MMWR ↗FDA EA ↗

Summary

Multi-state outbreak of E. coli O157:H7 linked to Chipotle Mexican Grill restaurants. Two outbreak strains were identified, suggesting two separate contamination events. Source investigation did not identify a single ingredient or supplier — the multi-matrix, multi-supplier structure of Chipotle's supply chain made source identification exceptionally difficult.

Traceback chain

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

farm [multiple — not identified] multiple ◼ 1 batch
processor [multiple — not identified] multiple ◼ 1 batch
distributor Chipotle's centralized distribution network national ◼ 1 batch
retailer Chipotle Mexican Grill restaurants national ◼ 1 batch

Known gaps: multiple ingredients from multiple suppliers; no single source identified

Sources