PRESENT STATUS OF THE PASTEURIZATION OF MILK 23 
THE NECESSITY FOR PASTEURIZATION 
As stated under Value of Pasteurization, there have been reported 
in the United States numerous epidemics of septic sore throat, 
typhoid fever, scarlet fever, and diphtheria, traceable to milk. 
Investigators have shown that the thermal death point of pathogenic 
bacteria is relatively low, and that where epidemics have been due to 
milk, efficient pasteurization was effective in controlling the spread 
of the epidemic through the agency of milk. 
The problem of pasteurization is not simply the question of which 
is preferable, raw or pasteurized milk, but rather, what is the most 
economical and practical way of producing and safeguarding a city 's 
milk supply. 
In connection with the possibility of transmission of disease through 
the agency of milk, the following fundamental facts must be recog- 
nized : 
(1) Certain diseases transmitted to man, such as tuberculosis and 
undulant fever, may come from diseased animals. The danger from 
this source can be minimized by the elimination of infected cattle 
from producing herds on the basis of tests devised for the purpose. 
(2) Freeing herds from infected cattle offers no protection against 
other diseases, such as typhoid fever, diphtheria, and septic sore 
throat, because the pathogenic organisms causing these diseases may 
come from infected water supplies or from human carriers of disease. 
It is manifestly impossible to examine medically all persons engaged 
in producing and handling milk. Yet such examinations at frequent 
intervals would be necessary, together with tests for the health of 
cattle, and the assurance of unpolluted water supplies on every farm 
in order to safeguard the general milk supply of the Nation to the 
same extent that is now possible through proper pasteurization. The 
appreciation of the need for pasteurization is distinctly shown by the 
marked increase in the use of pasteurization in the United States. 
LITERATURE CITED 
(1) Anonymous. 
1930. UNDULANT FEVER GERMS HARD TO KILL. Amei\ Jour. Pub. Health 
20: 160. 
(2) Anderson, A. K., and Finkelstein, R. 
1919. a study of the electro-pure process of treating milk. Jour. 
Dairy Sci. 2: 374-406, illus. 
(3) Ayers, S. H., and Johnson, W. T., Jr. 
1910. the bacteriology of commercially pasteurized and raw 
market milk. U. S. Dept. Agr., Bur. Anim. Indus. Bui. 126, 
98 p., illus. 
(4) and Johnson, W. T., Jr. 
1913. A STUDY OF THE BACTERIA WHICH SURVIVE PASTEURIZATION. 
U. S. Dept. Agr., Bur. Anim. Indus. Bui. 161, 66 p., illus. 
(5) and Johnson, W. T., Jr. 
1914. ABILITY OF STREPTOCOCCI TO SURVIVE PASTEURIZATION. Jour. 
Agr. Research 2: 321-330, iUus. 
(6) and Johnson, W. T., Jr. 
1914. THE DESTRUCTION OF BACTERIA IN MILK BY UITRArVIOLET RAYS. 
Centbl. Bakt. [etc.] (II) 40: 109-131, illus. 
(7) and Johnson, W. T., Jr. 
1915. ABILITY OF COLON BACILLI TO SURVIVE PASTEURIZATION. Jour. 
Agr. Research 3: 401-410, illus. 
(8) Johnson, W. T., Jr., and Davis, B. J. 
1918. THE THERMAL DEATH POINT AND LIMITING HYDROGEN ION CONCEN- 
TRATION of pathogenic streptococci. Jour. Infect. Diseases 
23: [290]-300, illus. 
