Isolation of Toxigenic Yersinia enterocolitica from Retail Pork Products

Abstract
Five of 69 (7%) processed and 63 of 128 (49%) raw retail pork products contained Yersinia enterocolitica. Thirty-two of 80 (40%) isolates were serotypable, with serotypes 0:3 and 0:5 occurring most frequently. All except one isolate of serotype 0:3 came from fresh pork tongues. Twenty-five isolates (32%) produced a heat-stable enterotoxin detected by the infant mouse and rabbit ileal loop assays. Live cultures in the rabbit ileal loop produced no response. Most of the serotype 0:3 (92%) and 0:5 (90%) isolates were mouse-positive, while most rhamnose-positive (89%) and citrate-positive (96%) isolates were mouse-negative.