Production is on hold at the Hungarian plant of the company linked to a deadly outbreak of Listeria monocytogenes from frozen vegetables in five European countries.

A spokesperson for Greenyard, a producer of fresh, frozen and prepared fruit and vegetables, told Food Safety News that the company is awaiting more data, information and analysis from the local authorities and EFSA (the European Food Safety Authority). The company is looking into alternative sourcing possibilities to supply customers.

“We have decided to put production on hold and are determined not to restart or release the freezing lines until we have found the root cause, and external experts, the local authorities and Greenyard are satisfied with the results of the further tests,” it said.  

“The full stop of the production will allow us to do a further in-depth review of the facility to find and eliminate the root cause.”

The outbreak has infected at least 47 and killed nine people in Finland, the United Kingdom, Sweden, Denmark and Austria. The suspected food source was initially believed to be just frozen corn but has now been expanded to include other frozen vegetables.

Eighteen of the cases have been reported this year, with the most recent person becoming sick in May. The outbreak is believed to have begun in 2015.

Greenyard said it has hired an external microbiologist as well as Campden BRI to advise and assist in taking appropriate measures, including environmental swabs and tests, dismantling and deep-cleaning of all equipment.

Campden BRI does not discuss work it is doing with clients because of corporate confidentiality.

Greenyard is also continuing to work with external laboratories and the authorities to further test and analyze the Hungarian plant following accredited methods (ISO 11290).

“All of our tests prior to June 29 were executed according to accredited methods (ISO 11290) and have been performed and analyzed by external laboratories since March 2018, and supervised by an external PhD microbiologist. In addition to this, our customers also perform their own respective tests and the authorities also conduct their own food safety tests,” said the company.

“We endorse the advice to cook frozen products until it has reached 70 degrees C and stayed at that temperature for at least two minutes. As a producer of frozen vegetable products, we recommend our customers to include cooking instructions on each packaging.”

Mitigation measures taken or ongoing include revision of the hazard analysis and critical control point (HACCP) system at the site, product labeled with clear instructions on the need to heat treat, a review of the water supply system, and revision of the microbiological control plan. 

Listeria monocytogenes IVb sequence type (ST) 6 that matches the outbreak strain from victims was isolated from frozen spinach and frozen green beans sampled at the facility in Baja. It was also isolated in a sample from a floor drain at the packaging area confirming the environmental contamination of the Hungarian processing plant.

Since March this year, the factory has been under increased official control and no frozen vegetables from the 2018 production season have been distributed.

In late June, the Hungarian Food Chain Safety Office banned the marketing of certain frozen products made by the plant between Aug. 13, 2016, and June 20, 2018. Authorities also ordered a product withdrawal and recall.

The plant is operated by 100 employees, excluding seasonal workers. The Greenyard spokesperson said “part of these” are working on the further testing, cleaning and disinfecting of the processing facility.

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