RT Journal A1 ROSANOFF AJ T1 IMmunity against tuberculosis in general paresis JF Journal of the American Medical Association JO Journal of the American Medical Association YR 1909 FD February 13 VO LII IS 7 SP 530 OP 531 DO 10.1001/jama.1909.25420330012002b UL http://dx.doi.org/10.1001/jama.1909.25420330012002b AB In our knowledge of immunity against infectious diseases no fact is more firmly established than that different individuals of the same species are apt to show different degrees of susceptibility to a given specific infection. In the case of tuberculosis this fact is commonly recognized even by the laity.The valuable results which have been obtained through experimental studies of immunity have stimulated interest in work in that direction; at the same time investigation of the nature of immunity of spontaneous occurrence has been somewhat neglected. And yet it may be that such investigation might throw light on some problems which experimental studies have failed to elucidate.In other words, it seems to me that a great deal might be gained if we should be enabled, by a study of cases, to arrive at a complete answer to the question: What circumstances have produced immunity against a given infection in