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The distribution of phage types among 221 human strains of Salmonella paratyphi A in Indonesia was studied. Approximately 50% were phage type 5, a rare type elsewhere in the world. Most other isolates were the cosmopolitan phage type 1. The ratio of phage type 1-5 was compared for two cities on Java, Jakarta and Yogyakarta. The ratios were significantly different, phage type 5 predominating in Jakarta. The ratio of phage types among 10 S. paratyphi A strains isolated from Jakarta river water was similar to that found in Jakarta patients.

The frequency distribution is presented of the Vi-phage types of Salmonella typhi and of the phage types of S. paratyphi A and S. paratyphi B, examined by the National Centres represented in the IFEPT from 1970 to 1974. The most common types encountered in this international study were A and E1 (= E 1 a), as has been previously observed. There was, however, a wide range of types, many of which are characteristic of particular geographical zones. The occurrence of such types out of their habitual context indicates their 'exotic' origin, providing a useful clue to their probable source. Plasmid-mediated chloramphenicol resistance appeared in epidemic typhoid fever for the first time during this period. It occurred in Mexico, India, Vietnam and Thailand, and has assumed important proportions. All the plasmids concerned belonged to compatibility group H 1. The study of this phenomenon continues, and the findings will appear in future reports.

Salmonella agona was isolated from an imported fish meal specimen and a Salmonella strain not listed in the Kauffmann-White Scheme was isolated from a shrimp specimen obtained from the Mediterranean coast of Lebanon. The biochemical and serological properties of the S. agona fish meal strain was identical to a standard strain. The serotype of the shrimp strain was O13,22 Vi. With the exception of hydrogen sulfide production the biochemical properties of the shrimp strain were similar to S. agona.

The natural occurrence of a strain of Salmonella enteritidis bioserotype Paratyphi-A is reported, in which the flagellar antigens segregated readily into normal phase 2 antigens and mixtures of normal phase 1 and phase 2 antigens, and in which phase variation of Andrewes was demonstrated with ease.