Susceptibility of wild mice to Yersinia pseudotuberculosis and Yersinia enterocolitica.

Laboratory-born progeny and adult populations of old world woods mice (Apodemus speciosus) trapped in a certain area where Yersinia pseudotuberculosis was prevalent among wild animals, were challenged with Y. pseudotuberculosis and Yersinia enterocolitica to determine the ecology of Yersinia in wild mice. The laboratory-born progeny population was associated with infection with Y. pseudotuberculosis but not with Y. enterocolitica serotype O:3 and was found to be nearly 200 times more susceptible to infection with Y. pseudotuberculosis than were the adult populations. A. speciosus convalescing from infection with Y. pseudotuberculosis showed protection upon subsequent challenge with homogeneous and heterogeneous serotypes of Y. pseudotuberculosis. These data suggest that the prevalence of Y. pseudotuberculosis in wild mice may begin with the infection in the newborn and thus spread to the Y. pseudotuberculosis naive adult mice populations.