I. TYPHOID FEVER IN CWI'MPANZEES ORALLY IN~ECTED WITH SALMONELLA TYPHOSA

Few infectious diseases of man have lent themselves to experimental study and reproduction in the laboratory animal with the classic simplicity and clarity that underlay the pioneer experiments of Pasteur and Koch on anthrax, rabies, and tuberculosis. Thus it was perhaps not too difficult for Koch to lay down his famous postulates; but it has not always been easy to follow them. In the case of typhoid fever--which has been the subject of our particular attention--the paucity of successful attempts to reproduce the disease has been striking in view of the 80 years that have passed since Klebs and Eberth first observed the typhoid bacillus. Although many experimental patterns, involving a variety of experimental animals, have been employed in laboratory studies of the pathogenic behavior of Salmondla typhosa, few investigators have attempted to reproduce the essential features of infection with this organism as observed in man: infection v/a the alimentary tract, invasion of the blood stream, and a marked, extensive and sustained enteritis. Friinkel and Simmonds (1), and later Remlinger (2) were apparently the first to claim success in the production of oral infection in laboratory animals with S. typhosa. In both rabbits and mice, ingestion of typhoid-contaminated food after 2 or 3 days of fasting was followed by enteritis, severe and frequently fatal septicemia, and engorgement or ulceration of the Peyer's patches (2). Griinbaum (3), by feeding typhoid cultures or infected stools to 4 chimpanzees, produced malaise, diarrhea, fever, a rising or positive Widal reaction, and