Source: Food Safety News

Company officials knew a Dole salad plant was contaminated with Listeria for a year and a half before they shut it down — then they only took action after the U.S. and Canadian governments traced a deadly outbreak to the facility.

Inspection reports (483) obtained by Food Safety News revealed the timeline of positive Listeria results and inaction. Dole Fresh Vegetables Inc. finally suspended production at its salad plant in Springfield, OH, on Jan. 21 this year after a random test by state officials showed a bagged salad contained Listeria monocytogenes.

By that time, at least 33 people in the U.S. and Canada had been sickened with the same strain of Listeria as was found when Ohio inspectors tested the Dole salad they collected from a retailer. All 33 victims had such severe symptoms they required hospitalization. Four of them died.

Dole restarted production at the plant in Springfield, OH, on April 21. Company officials won’t say what was done to clean the plant or how they plan to prevent future contamination there.

Inspectors from the U.S. Food and Drug Administration (FDA) checked the production plant three times in January and twice in February after genetic fingerprinting showed the undeniable link between the sick people and salads from the facility. They collected swab samples, unfinished product samples, testing records and other documents and information.

The FDA won’t comment on open investigations and would not make public the inspection reports on the Springfield processing plant. Thirty days after Food Safety News filed an FOIA request, the FDA mailed out the reports.

Who knew, and when did they know it?
According to the FDA’s inspection reports, in July 2014 Dole did swab tests of surfaces in the Springfield plant. The tests returned positive results for Listeria, but the facility kept producing salads, shipping them to dozens of states and at least five Canadian provinces.

At least five more times in 2014 and three times in late 2015 Dole’s internal tests showed Listeria contamination, but Dole kept the salad lines kept rolling until January this year.

The FDA inspection report states that Dole’s vice president for quality assurance and food safety, as well as the company’s quality assurance manager, were aware internal tests on Jan. 5 and 7 this year showed Listeria on equipment and other surfaces in the plant. But Dole continued to produce and ship salads.

The plant kept operating until Jan. 21. The following day Dole posted a recall notice with the FDA and the Canadian Food Inspection Agency (CFIA) for salads produced at the Springfield facility. Dole branded salads and house brands for Walmart, Kroger, Loblaws and Aldi were included in the recall.

Connecting the dots with DNA fingerprints
Outbreak investigators in the U.S. and Canada had been trying to find the source of the wide-reaching Listeria outbreak since September 2015. Scientists from the U.S. Centers for Disease Control and Prevention were working with FDA and the Canadian Food Inspection Agency. In January this year they happened upon the answer.

Samples of Listeria from outbreak victims — who became sick between May 2015 and January 2016 — had been subjected to genetic fingerprinting and added to pathogen databases. When the Listeria from the bagged salad randomly collected by Ohio inspectors was compared to the victims’ samples, the outbreak investigators had the break they needed.

As part of the outbreak investigation, FDA officials inspected the Dole plant on Jan. 16, 19 and 26, and again on Feb. 2 and 5.

On Jan. 16 FDA collected a sample of finished product in the form of a “Dole Salad Kit-Ultimate Caesar” and 16 sub-samples containing “in-process romaine lettuce used in the product from various stages of production, raw material through finished product packaging,” according to the inspection report.

“The finished product sample as well as the in-process and sub-samples collected from the water knife, the trans-slicer, and the metal tray beneath the cross-conveyor, all on Trim Line (redacted) were found by FDA laboratory analysis to be positive for Listeria monocytogenes.”

Not a new problem
Federal officials were apparently aware of problems at the Dole salad processing plant since at least March 2014. During inspections on March 17, 18 and 20 that year FDA personnel cited 16 problems that could contribute to food safety problems.

Those 16 specific problems were covered by three general observations:

  • Failure to maintain food contact surfaces to protect food from contamination by any source, including unlawful indirect food additives;
  • The plant is not constructed in such a manner as to allow floors and walls to be kept in good repair; and
  • Failure to provide adequate screening or other protection against pests

Among the specific problems cited were:

  • food residue on equipment after it had been sanitized;
  • standing water on floors;
  • cracks and holes in the floors;
  • peeling paint and rust; and
  • eroded floor around a drain.

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