Abstract
In the previous papers, it was reported that immunization of mice with living bacterial vaccine (attenuated S. enteritidis strain) was followed by strong active immunity to challenge infection with virulent strain 116-54. But the immunization of mice with killed bacterial vaccine was also effective to some extent to the challenge infection of S. enteritidis. Sixty per cent survival occured when vaccine and challenge dose were administered intraperitoneally. However, mice were not so resistant to intravenous challenge when vaccine was administered intraperitoneally. This facts suggested that some of immunity observed mightbe “immunity owing to the local resistance” in abdominal cavity.
Dr. Hazato reported the effectiveness of intravenous administration of killed vaccine.
In the present paper, bacteriological and histopathological studies of the intravenous administration of killed vaccine were described. It was confirmed that the effectiveness of the immunization with killed vaccine varied with the combination of the routes of administration of vaccine and challenge infection. And mice were most resistant to intraperitoneal challenge when vaccine was administered intraperitoneally. The nodules formed in the liver, spleen, and other reticuloendotherial systems after receiving killed vaccine, are qualitatively different from true typhom caused by the injection of living vaccine.
