An outbreak of gastro-enteritis due toSalmonella derby

An outbreak of Salmonella derby , involving sixty-eight patients, is described. 2. The organism was isolated from clinical cases, from carriers and also from dust in the wards, from a mouse and from a hand towel used by nurses. 3. The value of tetrathionate broth with subsequent cultivation on ‘SS’ agar as an aid to isolation of Salmonella bacilli was confirmed. 4. Cultural and biochemical characters of Salm. derby were recorded. 5. The antigenic structure of the isolated strains of Salm. derby was demonstrated, showing the presence of factor l and the absence of a minor flagellar antigen. 6. A serological response to Salm. derby infection was shown in patients, their sera containing H antibodies of a titre 1/20 to 1/320, whereas O agglutinins were absent at the time the tests were made. 7. Pathogenicity tests were performed on mice indicating the possibility of infection per os or by intraperitoneal injections. Mice were found to be potential faecal and urinary carriers.