As of a few days ago, this listeria cantaloupe outbreak has become the deadliest foodborne illness outbreak in 100 years. Yet, congress is silent.
As you might recall, the FDA, along with Colorado state officials, conducted an inspection at Jensen Farms and collected multiple samples, including whole cantaloupes and environmental (non-product) samples from within the facility, for laboratory analysis to identify the presence of Listeria monocytogenes. Of the 39 environmental swabs collected from within the facility, 13 were confirmed positive for Listeria monocytogenes with pulsed-field gel electrophoresis (PFGE) pattern combinations that were indistinguishable from three of the four outbreak strains collected from affected patients. Of the 13 positive environmental swabs, 12 were collected at the processing line and 1 was collected from the packing area. Cantaloupe collected from the firm’s cold storage during the inspection was also confirmed positive for Listeria monocytogenes with PFGE pattern combinations that were indistinguishable from two of the four outbreak strains.
FDA also identified the following factors as those that most likely contributed to the introduction, spread, and growth of Listeria monocytogenes in the cantaloupes:
Introduction:
• There could have been low level sporadic Listeria monocytogenes in the field where the cantaloupe were grown, which could have been introduced into the packing facility
• A truck used to haul culled cantaloupe to a cattle operation was parked adjacent to the packing facility and could have introduced contamination into the facility
Spread:
• The packing facility’s design allowed water to pool on the floor near equipment and employee walkways
• The packing facility floor was constructed in a manner that made it difficult to clean
• The packing equipment was not easily cleaned and sanitized; washing and drying equipment used for cantaloupe packing was previously used for postharvest handling of another raw agricultural commodity
Growth:
• There was no pre-cooling step to remove field heat from the cantaloupes before cold storage. As the cantaloupes cooled there may have been condensation that promoted the growth of Listeria monocytogenes
With 2010 and 2011 audits of Jensen Farms that gave them high marks (see above 96), one would think that that committee would be interested in asking why the differing views of the same facility by the auditor and the FDA? That is why I wrote this letter.