Serum resistance of Yersinia enterocolitica expressed in absence of other virulence markers.

Serum resistance of Yersinia enterocolitica after growth at 37 and 25 degrees C appears to be specific for serogroup O:3 and appears to be expressed even in the absence of other phenotypic virulence-associated markers, such as the presence of V antigen, autoagglutination, and calcium dependency after growth at 37 degrees C.