239 
fection and the diminished resistance offered by the sick, there can be 
no doubt that the contamination of milk is a factor that plays a part 
in keeping* up the rate of sickness and death. 
MILK AND TUBERCULOSIS. 
The report of the United States Census Office on mortality for the 
year 1905 shows that deaths from all causes in the registration area 
were in the proportion of 1,616 per 100,000. Tuberculosis in all its 
forms caused 193.6 deaths per 100,000. Applying the same rate 
throughout the United States , it may be justly estimated that tuber- 
culosis causes over 160 ,000 deaths a year in the United States. 
At the International Congress on Tuberculosis held in London in 
1901, Koch made the announcement that bovine tuberculosis is trans- 
missible to the human subject to only a slight extent if at all. The 
doubt thus cast on the relation between cow’s milk and tuberculosis 
has to a great extent disappeared on further investigation made by a 
host of observers, most prominent among whom is von Behring, who 
claims that milk fed to infants is the chief cause of tuberculosis in 
man. 
Schroeder and Cotton in a recent bulletin of the Bureau of Animal 
Industr}^ conclude that the assertion that tuberculosis is a negligible 
quantity in the measures that must be taken for the preservation of 
human health is without basis and that there is no more active agent 
than the tuberculous cow for the increase of tuberculosis among ani- 
mals and its persistence among men. 
The rarity of primary intestinal tuberculosis, on which subject 
there is a discrepancy of statistics, is not in favor of the theory of 
infection by ingestion. It has been, however, repeatedly proved that 
tubercle bacilli may pass through a mucous membrane without leav- 
ing traces at the point of entrance. Again it has been demonstrated 
by competent observers that tubercular infection may take place 
through the tonsils. Latham estimates that not less than 25 to 30 per 
cent of the cases of tuberculosis which occur in early childhood are 
due to intestinal, and therefore presumably to food, infection. Of 
deaths in 1905 from all forms of tuberculosis in the registration area 
of the United States, about 1 in 39 was among infants under 1 year 
and 1 in about II among children under 5 years of age. 
R a vend writing in 1898 says : 
In northern Norway, Sweden, Lapland and Finland where reindeer con- 
tribute the bulk of farm animals, or about Hudson Bay and the islands of the 
Pacific, where there are only a few cattle, tuberculosis is far less prevalent in 
man. In Algiers the cattle are few and live for the most part in the open air 
and away from cities and it is found that tuberculosis does not increase among 
the natives. In Italy, on the ether hand, where cattle are housed, Perroncito 
states that tuberculosis has become the scourge of man and beast. 
