Listeria outbreak source identified

Officials announced Wednesday that they had traced a deadly, multi-state listeria outbreak back to a cantaloupe packing shed in Colorado, The New York Times reports.

At least 25 people have been killed in the outbreak, the deadliest of its kind in 25 years.

“You’re rolling around cantaloupe on uncleanable equipment, and you’re getting it wet and you’re not cooling it. It provides the perfect environment for listeria growth and spread,” James Gorny, a senior food safety advisor at the Food and Drug Administration, told the Times. 

Jensen Farms, in the southwest region of Colorado, was implicated in the outbreak soon after it began, in early September. In a news release issued Wednesday, the Food and Drug Administration pointed to the packing facility’s design, which "allowed water to pool on the floor near equipment and employee walkways," and the packing facility's floor, which "was constructed in a manner that made it difficult to clean."

How the listeria got into the facility in the first place is still unclear. It could have come from the fields where the cantaloupe was grown, or from a truck used to haul cantaloupe that was parked nearby.

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The Wall Street Journal reports that in a letter to Jensen Farms, the FDA said that 13 of 39 tests for listeria on equipment at the facility came back positive for the bacteria.

According to the Times, just days before the outbreak began, the farm had received a score of 96 points out of 100 in a food safety audit conducted by an outside contractor.