580 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1921. 



cities of Mexico. Therefore Ricketts and his colleague, Wilder, went 

 to the City of Mexico and carried on their experiments which resulted 

 in the establishment of the fact that typhus is communicated by the 

 body louse, the results being published in 1910. The Frenchmen, 

 Nicolle, Comte, and Conseil, working in Tunis, had reached similar 

 results the year previously, and the discovery was confirmed soon 

 after by Anderson and Goldberger of the United States Public 

 Health Service. 



The causative organism of typhus is still an undecided question. 

 Several different microorganisms have been found both in typhus 

 patients and in lice, but that anyone of them is the actual cause of 

 the disease is still disputed. That the disease is transmitted by the 

 bites of lice is now thoroughly accepted, but with the microorganism 

 still in doubt the question of its partial development in the bodies of 

 the lice is also still in doubt. Several workers have claimed that the. 

 disease is transmitted hereditarily by lice while this has been dis- 

 puted by other equally competent authorities. That the absolute de- 

 struction or prevention of lice will ward off typhus is beyond doubt. 



Never in the history of the world have there been such opportuni- 

 ties for the demonstration of the value of a prophylactic measure as 

 the Great War afforded with this disease. The epidemic which began 

 in Serbia in January, 1915, spread all over the country. The neces- 

 sary sanitary measures with regard to cleanliness and louse destruction 

 and prevention were unknown, apparently, in that country, and the 

 majority of the native physicians were soon taken with the disease 

 and died. The American Red Cross then stepped in, and American 

 physicians were sent to Serbia, and although by April of 1915 people 

 were dying at the rate of 9,000 a day, the epidemic was measurably 

 controlled. After the Russian Armies mobilized, typhus appeared 

 and the dread disease was more or less prevalent all along the eastern 

 front. Russian prisoners in German detention camps spread the 

 disease and its obvious prophylaxis was put into effect by German 

 physicians, and the life history of the body louse was carefully 

 studied by Haase, a competent entomologist. By strenuous efforts 

 the disease was prevented from making inroads in the armies of 

 the Allies, although it was impossible to keep the troops at the front 

 free from lice; and that brings us, although chronologically out of 

 order, to the subject of another louse-borne disease, namely, Trench 

 Fever. 



In the early part of the war a young American physician, Dr. 

 Plotz, had been studying a fever in New York City known as Brill's 

 Disease, and had supposedly isolated the causative organism. Symp- 

 tomatically this disease is closely related to typhus fever, resembling 

 a mild form of that malady and is louse-borne. The fever which 

 developed among the troops in the trenches resembled the disease 



