Cases of Enteric in Native Sepoys

In the still prevailing uncertainty as to the incidence of enteric fever among Natives of India, the following notes may be found of interest.* They include a few observations 011 the reaction between the serum of healthy men and an emulsion of dead B. typhosus as tested by the sedimentation method and also a brief description of a few cases of enteric fever met with in the past 18 months with the reasons more or less adequate on which the diagnosis was made either during the course of the illness or subsequently. I. First as regards the serum of healthy men. The men chosen for experiment were all recruits or sepoys of the 3rd P. I. between nineteen and 22 years of age, all Brahmins from Unao and neighbourhood. They were, as far as we knew, free from disease of any kind. The serum of 20 cases was put up with typhoid emulsion supplied by the Research Laboratory, Bombay, in dilutions of 1?4, 1?8, and 1?16. After standing for 24 hours, all the specimens shewed a fairly complete degree of sedimentation by the 1?4 dilution ; six an appreciable degree by the 1?8 dilution ; and two a certain though much less complete sedimentation by the 1?16 dilution. These last two were again, put up in dilutions of 1 16, 1?24, and 1?48, but in both cases the 1? 24'dilution failed to affect the typhoid emulsion, within 24 hours, though, again, the 1?16 dilution gave a marked though incomplete positive result. Assuming then that the number is not too small to admit of any trustworthy deduction beinodrawn, I am led to the conclusion that a positive result with this test at a higher dilution than 1 24 may be taken as evidence of an attack of enteric fever either at the time of