Experts used whole genome sequencing to identify the food source, which initially was thought to be limited to frozen corn. As of 8 June 2018, 47 cases (including 9 deaths) have been reported.
The same strains of L. monocytogenes have been detected in frozen vegetables produced by the same Hungarian company in 2016, 2017 and 2018. This suggests that the strains have persisted in the processing plant despite the cleaning and disinfection procedures that were carried out.
The available information confirms the contamination at the Hungarian plant. However, further investigations, including thorough sampling and testing, are needed to identify the exact points of environmental contamination at the plant.
According to foodpoisonjournal.com, on 29 June 2018, the Hungarian Food Chain Safety Office banned the marketing of all frozen vegetable and frozen mixed vegetable products produced by the affected plant between August 2016 and June 2018, and ordered their immediate withdrawal and recall. This last measure is likely to significantly reduce the risk of human infections and contain the outbreak. All freezing activity at the plant has been stopped.
