Occurrence of pathogenic Yersinia enterocolitica in Norwegian pork products determined by a PCR method and a traditional culturing method

From October 1997 to April 1998, a survey was conducted to assess the occurrence of pathogenic Yersinia enterocolitica in Norwegian pork products, using a traditional culturing method and a PCR assay. A total of 300 pork samples was examined. Five slaughterhouses in the Norwegian Meat Cooperative were represented with 249 samples and another 51 samples were obtained from retail outlets in the city of Oslo. Using the NMKL method, Y. enterocolitica 0:3 was isolated from six (2%) of the samples, while the PCR method indicated presence of pathogenic Y. enterocolitica in 50 (17%) of the samples. The results indicate that a reduction has occurred in the prevalence of pathogenic Y. enterocolitica in Norwegian pork products, as compared to a previous Norwegian study conducted in 1988-1989. The study also highlights the need for further development and improvement of methods applied for the detection of pathogenic Y. enterocolitica in foods.