New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1903-10-06
HOW TUBERCULOSIS is SPREAD.

In the prevention of disease Of any kind the
first great step is TO ascertain how 1t is trans
mitted from one victim TO another. 10 lhe
methods whereby the germs of tuberculosis are
disseminated a great deal of attention has al
ready been devoted, but without complete
agreement in the conclusions of experts. Such
differences Of opinion as still exist regarding
a malady from which the mortality is greater
than from any other Except possibly pneu-
monia) lend importance TO every fresh effort
10 get nearer TO the truth, especially if a COM
paratively new suggestion results therefrom
This is the case with discussion of the mat
fer in the pages of 1.-The New-York Medical
Journal" by DR.. J. o. Cobb, of the United States
Marine Hospital Service, and his paper will
doubtless receive the consideration which 1t
deserves.
The principal modes of infection which have
been held responsible for the spread of tuber-
cuIosis are breathing contaminated air and con-
suming contaminated food. DR.. Cobb once be-
lieved the former TO be the more serious Of the
two, but now lays the chief stress Oh the latter
He comedies that it is possible for particles of
solid matter, like SCOT, to reach the innermost
air cells of the lungs, but he thinks that the
chance of their getting there is small. 1t will
not do he says, to infer too much about the
route by which q germ enters the body from
as TO the exclusiyeness of Inhalation as the
means of trouble is further strengthened by n
variety of facts which show that bacilli can get
into the lung tissue from the blood.
Positive evidence that they do so Is not lack
ing. In many laboratory experiments with
guinea pigs tuberculous matter is introduced
into the abdominal cavity by incubation. Shortly
afterward the lungs also prove TO be infected
Two Investigators, Nicolas and Descar, admin
istered TO hungry dogs food containing a great
number of germs, and within a few hours found
some of the latter in the thoracic duct the canal
which conveys the products of digestion TO the
circulatory system. Though feeling that these
latter tests need repetition before they can be
regarded as conclusive, DR.. Cobb is evidently
strongly impressed by them.
The way is now made clear for what is the
most interesting and original of his opinions.
Dr. Cobb suspects that ordinary articles of food
are often so carelessly exposed that flies can
visit them after having Lit on infected sputum.
The belief that cholera and typhoid germs are
transmitted TO edibles in a similar way is now
commonly entertained by physicians, and it is
credible that those OF tuberculosis are thus dis
seminated with even greater frequency Dr.
Cobb goes far as to make this the chief
process of infection among human subjects He
does not hold milk entirely innocent, but the
large number or deaths IN countries like China
and Japan, where that article of diet has a
limited use, leads him to minimize the danger
from it in countries like the United States
Among cattle. as with human subjects, the
infection of food with sputum is adopted as the
true explanation of the spread OF tuberculosis
The distribution OF germs may be effected by
coughing. If the animals are confined in a
stable; and if healthy cows should lick out feed
boxes previously used by sick ones the conse-
quences would be the same. Dr. Cobb notes
that even OH large ranges. where the open air
apparently precfides the possibility of mischief
through inhalation, tuberculosis occasionally de-
velops, and he fancies that the common resort
Of many animals to a single block Of rock salt,