Yersiniosis is a type of gastroenteritis (gastro) caused by the (germ) bacterium Yersinia. Yersiniosis can affect anyone, however, it is more common in young children. Yersiniosis occurs when Yersinia bacteria are taken in by mouth. Yersinia bacteria are found in wild, farm and pet animals and birds, particularly chickens and pigs.
Y. enterocolitica belongs to a family of rod-shaped bacteria. Other species of bacteria in this family include Y. pseudotuberculosis, which causes an illness similar to Y. enterocolitica, and Y. pestis, which causes plague. Only a few strains of Y. enterocolitica cause illness in humans. The major animal reservoir for Y. enterocolitica strains that cause human illness is pigs, but other strains are also found in many other animals including rodents, rabbits, sheep, cattle, horses, dogs, and cats. In pigs, the bacteria are most likely to be found on the tonsils.
The most common symptoms of this disease are diarrhoea, fever, and vomiting.
Isolation of the organism from stool, blood, bile, wound, throat swab, mesenteric lymph node, cerebrospinal fluid, or peritoneal fluid. If yersiniosis is suspected, the clinical laboratory should be notified and instructed to culture on CIN agar.
Most infections are self-limited. Antibiotics should be given for severe cases. Y. enterocolitica isolates are usually susceptible to trimethoprim-sulfamethoxazole, aminoglycosides, third-generation cephalosporins, fluoroquinolones, and tetracyclines; they are typically resistant to first-generation cephalosporins and most penicillins. Antimicrobial therapy has no effect on postinfectious sequelae.
Yersinia enterocolitica O:9 infections were reported in Auvergne, France, in 1988 to 1989, while brucellosis due to Brucella abortus was almost eliminated. The serologic cross-reactions between the two bacteria complicated the diagnosis of brucellosis cases. In 1996, human cases of Yersinia enterocolitica O:9 infection were detected, with a peak incidence of 12 cases.