Yersinia enterocolitica outbreak associated with ready-to-eat salad mix, Norway, 2011.

In 2011, an outbreak of illness caused by Yersinia enterocolitica O:9 in Norway was linked to ready-to-eat salad mix, an unusual vehicle for this pathogen. The outbreak illustrates the need to characterize isolates of this organism, and reinforces the need for international traceback mechanisms for fresh produce.

Yersinia enterocolitica O:9 infections associated with bagged salad mix in Norway, February to April 2011.

In March 2011, the Norwegian Institute of Public Health identified a possible outbreak involving 21 cases of Yersinia enterocolitica O:9 infection with similar MLVA-profiles. Preliminary results of epidemiological and microbiological investigations indicate bagged salad mix containing radicchio rosso (also known as Italian chicory) as a possible source. As a result of the investigation, bagged salad mixes of a specific brand were voluntarily withdrawn from the market by the producer.

Antibacterial activity of sphagnum acid and other phenolic compounds found in Sphagnum papillosum against food-borne bacteria.

Aims: To identify the phenolic compounds in the leaves of Sphagnum papillosum and examine their antibacterial activity at pH appropriate for the undissociated forms.

Methods And Results: Bacterial counts of overnight cultures showed that whilst growth of Staphylococcus aureus 50084 was impaired in the presence of milled leaves, the phenol-free fraction of holocellulose of S. papillosum had no bacteriostatic effect.

Sphagnan--a pectin-like polymer isolated from Sphagnum moss can inhibit the growth of some typical food spoilage and food poisoning bacteria by lowering the pH.

Aims: Investigate if the antibacterial effect of sphagnan, a pectin-like carbohydrate polymer extracted from Sphagnum moss, can be accounted for by its ability to lower the pH.

Methods And Results: Antibacterial activity of sphagnan was assessed and compared to that of three other acids. Sphagnan in its acid form was able to inhibit growth of various food poisoning and spoilage bacteria on low-buffering solid growth medium, whereas sphagnan in its sodium form at neutral pH had no antibacterial activity.

Characterization of spore appendages from Bacillus cereus strains.

Aims: Further characterization and comparison of spore appendages from Bacillus cereus strains.

Methods And Results: Appendages were isolated from 10 B. cereus strains from the food industry and food-borne outbreaks.