Cause of cantaloupe Listeria outbreak narrowed
Oct. 19, 2011
by Keith Nunes
WASHINGTON — The Food and Drug Administration has narrowed the possible cause of the Listeria outbreak associated with whole cantaloupes to two possible factors: low level sporadic Listeria monocytogenes in the field where the cantaloupe were grown, which may have been introduced into the packing facility, and a truck used to haul culled cantaloupe to a cattle operation that was parked adjacent to the packing facility and may have introduced contamination into the facility.
The F.D.A. said the Jensen Farms cantaloupe packing facility’s design allowed water to pool on the floor near equipment and employee walkways and that may have contributed to the spread of the pathogen in the facility. In addition, the agency said the packing facility’s floor was constructed in a way that made it difficult to clean; and the packing equipment was not easily cleaned and sanitized. In addition, washing and drying equipment used for cantaloupe packing previously was used for postharvest handling of another raw agricultural commodity. The F.D.A. did not identify the other commodity.
There was no pre-cooling step to remove field heat from the cantaloupes before cold storage, and the F.D.A. said that as the cantaloupes cooled there may have been condensation that promoted the growth of Listeria monocytogenes.
The cause of the multi-state Listeria outbreak associated with whole cantaloupes that has caused 123 illnesses and 25 deaths as of Oct. 17 has befuddled the F.D.A. The agency said its findings regarding the outbreak highlight the importance for companies to employ good agricultural and management practices in their packing facilities as well as in growing fields. The F.D.A. recommended that companies employ good agricultural and management practices for the growing, harvesting, washing, sorting, packing, storage and transporting of fruits and vegetables sold to consumers in an unprocessed or minimally processed raw form.
The F.D.A. issued a warning letter to Jensen Farms on Oct. 18 based on environmental and cantaloupe samples collected during the inspection. The agency also said it still considers the investigation to be open.