July 28, 1916] 



SCIENCE 



123 



ning delirium, and other symptoms char- 

 acteristic of typhoid, disappear, or are 

 markedly ameliorated. Perhaps the most 

 important result produced is that the blood 

 usually becomes free from bacteria follow- 

 ing a single injection. In forty per cent, of 

 the cases, this return of temperature to 

 normal is permanent, and the patient re- 

 mains symptomatically, and to all intents 

 and purposes, well. The temperature may 

 fluctuate for a day or two and then become 

 normal. This forty per cent, of aborted 

 cases, as we call them, actually about 

 twenty-five in our series, were restored to a 

 permanent normal condition within a week 

 after beginning treatment. About twenty- 

 five per cent, more are markedly bettered, 

 but not so rapidly cured ; the course of these 

 ameliorated cases is characterized by a per- 

 manent drop of say a degree in temperature 

 following each injection, and the average 

 duration of the disease in this category is 

 distinctly shorter than is usual. There re- 

 main, however, a third of our cases, which 

 total sixty-two, in which the intravenous 

 vaccine treatment has produced no demon- 

 strable effect. These cases are usually 

 severe ones from the onset and it is impos- 

 sible to say that the treatment did not pre- 

 vent an even more serious course than the 

 one observed. At least it may be said that 

 the treatment does no harm in these cases, 

 and is followed by temporary abatements of 

 fever and symptomatic benefit. There is a 

 significant blood picture in this class of un- 

 affected cases ; they are found to differ from 

 those that are benefited by the treatment 

 in the weakness of antibodies present in the 

 serum. Mention has already been made as 

 to the occurrence and diagnostic value of 

 certain of these antibodies or agglutinins in 

 typhoid fever. We believe from our study 

 that a certain concentration of these anti- 

 bodies is necessary to assure recovery or 

 benefit after the vaccine injection which, as 



has been mentioned, produces an increase in 

 the leucocytes. Our present conception of 

 the mechanism of the rapid cure that is fre- 

 quently produced is that it is due to the 

 combination of these two factors, increased 

 leucocytes and antibodies already present 

 in the body. In other words, when the pa- 

 tient is fighting the infection successfully, 

 a sudden call on his reserves, the phago- 

 cytes, finally routs the invader. It may be 

 possible to supply these antibodies when 

 they are lacking by serum from immune 

 animals, and this is one of the many prob- 

 lems connected with this disease on which 

 we are now engaged. 



I have tried to lead you into full view 

 of the firing-line of the forces attacking 

 typhoid fever. You will perceive that much 

 remains to be done in the line both of pre- 

 vention and of cure, but you will not fail, I 

 am sure, to share my belief that here is one 

 of the major diseases which will eventually 

 disappear. I have endeavored to show you 

 the vulnerable points in its cycle of devel- 

 opment. If individual cases be rapidly 

 cured, much suffering and death will be 

 prevented and great economic loss avoided ; 

 the period of dissemination of the disease 

 germs will also be greatly shortened. 

 Again, if comprehensive sanitary regula- 

 tions safeguard the disposal of excreta 

 from typhoid fever cases, detect and elimi- 

 nate the carrier, and prevent the contami- 

 nation of food and drink, the continuity of 

 the disease will also be interrupted. Thor- 

 ough prophylactic immunization of large or 

 entire communities will not only protect 

 most of the vaccinated individuals, but pre- 

 vent foci for further spread of the disease. 



You will appreciate the inequality in the 

 utilizable knowledge of typhoid fever that 

 has been acquired through the two different 

 types of medical advance. The purely ob- 

 servational, bedside, clinical progress, re- 

 sulted, after the lapse of centuries, in cri- 



