Immunological Distinctions of Two Strains of the Mouse Typhoid Group Isolated during Two Spontaneous Outbreaks among the Same Stock

Two strains of the paratyphoid B-enteritidis group causing separate epidemics of mouse typhoid among 2,500 to 4,000 cancer breeding mice are found to be antigenically different. Mouse Typhoid I, isolated from the first outbreak, is related but not identical with two strains of enteritidis, while Mouse Typhoid II is related to but not identical with the human paratyphoid B strains. In a separate paper in this series, Webster has identified Mouse Typhoid II strain with Bacillus pestis caviae Smith and has suggested its close relation to the Bacillus aertrycke (mutton) group of Schütze.