Independent testing in Finland and Switzerland of a variety of products detected Listeria monocytogenes last year. However, no samples contained the pathogen at levels above legal limits.
The Finland customs authority detected Listeria monocytogenes in imported frozen fruits, berries and vegetables. In Switzerland, the bacteria was found in some ready to eat foods. It was the first time in the Finnish custom authority’s laboratory microbiological studies that Listeria had been detected in frozen fruit. The Customs Laboratory examined 78 lots of frozen fruit and detected Listeria in eight of them but levels were not above the regulatory limit.
As limits were not exceeded, the customs authority did not prohibit the import or placing on the market of frozen fruit. However, they issued a notice to importers about the presence of Listeria. Intensified checks for Listeria in frozen fruit will be done this year.
In frozen vegetables, the Customs Laboratory detected Listeria in 18 batches of 80 items studied. However, concentrations remained below the maximum level of less than 100 colony forming units per gram set by European regulation.
Two corn samples showed the same Listeria strain that caused an outbreak where 54 people fell ill in six countries and 10 died since 2015. A Hungarian frozen vegetable factory, owned by Greenyard Group, was the source of contamination.
Meanwhile, an analysis for Listeria in ready to eat (RTE) foods in Switzerland last year detected the bacteria in 3 percent of samples. The Association of Cantonal Chemists of Switzerland (ACCS) conducted a national screening campaign collecting 1,000 samples of RTE foodstuffs mostly of vegetable origin including salads and fruit. The group said RTE products are becoming more popular in Switzerland and such items are regularly reported as being contaminated with Listeria monocytogenes.