Pathogenic properties of Yersinia enterocolitica.

A total of 88 isolates of Yersinia enterocolitica was examined for heat-stable enterotoxin production and ability to penetrate HeLa cells and evoke keratoconjunctivitis in guinea pigs (Séreny test) as potential pathogenic properties. All 49 isolates belonging to serotypes O:3, O:8, O:9, and O:5,27 and only 5 of 39 strains of other serotypes were HeLa positive. Séreny-positive strains were found only in serotype O:8. Heat-stable enterotoxin production was almost ubiquitous in all serotypes. Y. enterocolitica strains were classified into five groups with regard to their potential pathogenic properties.