216 BACTERIOLOGY 



In some countries, as in Germany, for example, where the larger 

 cities and towns are supplied in the main with water of a highly 

 satisfactory character, there still remains a notable residue of cases 

 of typhoid fever. These, we know, are due to contact infection, to con- 

 tamination of raw foods, such as milk, oysters, and the like, to the 

 conveyance of the specific germ on the bodies of flies, and to similar 

 modes of dissemination. 1 It is a fact full of significance that the ex- 

 istence of these various modes of spread is recognized, that they are 

 held to be matters of public concern, and that preventive measures 

 are being instituted under expert bacteriologic control for suppressing 

 the existing sources of infection. One of the most difficult problems 

 in this campaign lies in the prompt recognition and rigorous super- 

 vision of the mild and obscure cases. It may be comparatively simple 

 to isolate and disinfect with thoroughness in the franker types of the 

 disease, but it is not clear that the danger is most critical on this side. 

 The application of searching and delicate bacteriologic tests is often 

 necessary to determine the suitable mode of action. The dependence 

 of public hygiene upon bacteriologic data and methods has rarely 

 been better exemplified. 



The vigorous warfare that is being waged against malaria in many 

 tropical countries affords a further and striking illustration of the 

 utilization of existing resources for the avoidance of specific infection. 2 

 It is hardly necessary to reiterate the obvious truth that malaria con- 

 stitutes the chief and, perhaps, the only serious obstacle to the colon- 

 ization of the tropics by the white races. Political and economic 

 questions of the gravest import to mankind are bound up with the 

 fortunes of a protozoon and a mosquito. The complex life-cycle of 

 the malarial parasite offers an unusual number of points of attack. 

 As is well known, several distinct views are current as to the best way 

 of interrupting the continuity of transfer between man and the mos- 

 quito. It is conceivable that by the destruction of the malarial para- 

 site within the body of man, the supply of parasites for the mosquito 

 may be cut off and the circle broken at this point. If the mosquitoes 

 are prevented from becoming infected, man is safe. It is claimed by 

 the adherents of one school that this method has proved very effect- 

 ive in certain localities where it has been systematically employed. 

 The extermination of the parasite in the blood of man by the admin- 

 istration of quinin certainly constitutes an important weapon in the 



1 Schuder, Zur Aetiologie des Typhus, Zeit. f. Hyg., 38, p. 343, 1901. 

 Hutchinson, R. EL, and Wheeler, A. W., An Epidemic of Typhoid Fever due to 



Impure Ice. American Journal of Medical Science, 126, p. 680, 1903. 



Ficker, M., Typhus und Fliegen, Archiv. f. Hyg., 46, p. 274, 1903. 



Hamilton, A., The Fly as a Carrier of Typhoid, Journal of the American Medical 

 Association, n. 577, 1903. 



Newman, G., Channehof Typhoid Infectionin London, Practitioner, 72, p. 55, 1904. 



2 Die Bekampfung dcx Malaria (Koch, R., und Ollmig), Die Malariabekamp- 

 fung in Brioni (Frosch, P.), in Puntacroce (Bludau), in der Maremma Toscana 

 (Gosio, B.), etc., Zeit. f. Hyg., 43, 1903, Heft 1. 



