In the last few years a group of organisms resembling Yersinia pseudo-tuberculosis has been isolated from diarrhea and other diseases of man. This group has been named Yersinia enterocolitica. These organisms have also been isolated from a wide range of wild and domestic animals. Although no epidemiological connection has been established, it is likely that human’s infections are directly or indirectly derived from animal sources and may be contracted through the ingestion of contaminated food.
Like Yersinia pseudo-tuberculosis, for which it may have been mistaken in the past, Yersinia enterocolotica is motile when grown at 220C, but the two species differ from one another in some respects. Although the pathogenicity of the organism has not been finally established, there is evidence to suggest a relationship between its presence and the symptoms of disease.
It has been isolated from patients with acute terminal ileitis, mesenteric adenitis, appendicitis and erythema nodosum, as well as from those with mild and severe gastroenteritis. Human infections have been reported mainly from Sweden and Belgium where they have been most looked for, but also from other European countries including Britain and from other parts world like Central Africa: they are probably much more common and widespread than is presently realized.