Risk of Yersinia infection among butchers

The purpose of this study was to evaluate the risk of yersinia infection among butchers. Serum samples were collected from 146 abattoir workers, stratified into 3 groups according to exposure to swine throats and intestines. 100 healthy blood donors were used as controls. Antibodies against Yersinia enterocolitica O:3 and O:9 and Y. pseudotuberculosis I and III were measured using ELISA. Symptoms associated with yersiniosis were recorded in a questionnaire. Antibodies against Y. enterocolitica O:3 were observed more often in the sera of abattoir workers (19%), especially in butchers handling swine throats and intestines (27%), than in the sera of healthy blood donors (10%). During the 6 months preceding this study, 30-40% of the workers reported symptoms of abdominal pains and diarrhoea. However, the symptoms did not correlate with the occurrence of antibodies. One butcher had developed a yersinia-triggered prolonged reactive arthritis. Tonsil samples were collected from 120 pigs to determine the extent of yersinia contamination. Positive isolates were obtained from 54 pigs (45%). Y. enterocolitica O:3 was isolated from 31 pigs and Y. pseudotuberculosis III from 11 pigs. All of these strains shared characteristics typical for virulent strains. We conclude that yersinia infections are an occupational health risk to workers slaughtering swine in the abattoirs.