Gloucester County Democrat., 1909-04-15
TUBERCULOSIS.
An Address to Cheshire Farmers
Association, England.
TBy Sir j. M'Fadyean.


brief resume of the growth of our
and some characteristics of the mi
crobe.
Parasitic Nature of Tubercle Bacillus.
What ever might have been their ex-
1istence in the past, they were now able
to multiply only inside the bodies of
men or animals. It might be asserted
without fear of contradiction that if
the higher animals and man were from
any cause to become extinct, so would
the tubercle bacillus. 1t would die
with them, because it was SO consti-
tuted that it was quite unable to multi
ply except in the bodies of animals and
men that were susceptible to it. A very
important consequence followed from
that, and it was that tuberculosis,
whether in animal or man, was pow
erful, contagious or infectious disease,
and it was a very important fact to
realize that the tubercle bacillus was
not able to multiply in dead mat
ter outside the body.
Tuberculosis Contagious Disease.
If followed that every case of tuber-
culosis originated in man or animal
must be due to the introduction into
the previously healthy patients body
of germs which we're bred in the body
of previous case. He asserted most
confidently that such was the case
Naturally they would be disposed to
ask what was the evidence of that very
dogmatic statement. Investigation
showed that the tubercle bacillus could
not be induced to grow at all unless
one employed tempature of ninety
degrees Fahrenheit. That was an un-
natural temperature except in the
tropics. But even when one had got
temperature of ninety they could not
induce the tubercle bacillus to grow
or multiply at all unless it was in GER
tain very special soil or media. That
by itself was evidence quite sufficient
to show that under natural conditions
the bacillus could not multiply outside
the body, and if a case arose it must
be in consequence of the Introduction
into the body of bacillus that was
bred in body of an antecedent case.
The more any particular class of ami
NAL was shielded from tubercular sub
jects, then in the same proportion the
class remained free from the disease.
rf'ttbesesz1 aSiS alnacat 5SpknnWIss
among wild animals, or animals that
/ were kept in a state of nature The
habits of the wild animals to a large
extent shielded them from the tend
ency which the disease had to spread
from a diseased animal to any other
of the same species brought into con-
tact with it.
In spite of the fact that tuberculosis
was common in cattle it was practi-
cally unknown in sheep. The only ex-
PLANTATION to suggest itself with regard
to that fact was that sheep did not
take tuberculosis at all, just in the
same way that human beings did not
/ take swine fever. That was not the
true ex PLANTATION, because it had been
shown that if they took sheep and at
tempted to infect them with tuber-
culosis of cattle they contracted the
disease, and readily so. Some other
explanation must therefore be found,
and to him there seemed to be no
doubt at all that tuberculosis never
originated spontageously in any class
of animals, but rather that the condi-
tions under which they were kept
made it very likely that the bacillus
would be passed on from one animal
to another.
When the tubercular bacillus was
introduced into the animal it started
to multiply, and in so doing it manu-
| factured certain substances which
were practically of the nature of poi-'
sons to the animal tissues in its i'm
mediate neighborhood, and in this way
it irritated the tissues and led to the
development of the disease in the
lungs and various other organs of the
body.
LOcaIisation of the Disease.
But there was one important diff
ference between the tubercle bacillus
and many other bacilli, and that was
that it did not form very much poison
which was apt to get absorbed into
the system and affect the whole con-.
stitution of the animal. The tend
ency rather was to act in the imme-
diate neighborhood where it was grow
ing, and thereby hanged an important
point, which was that unless the tu-
bercle bacillus happened to be grow
ing in what might be called vital or
gan it might grow long time without
sensibly affecting the animals gem
era1 health. That was the explanation
why in slaughter houses one might
find an animal which before it was
killed appeared to be in the pink of
condition and yet when it was post
mortened' was found to have extern
siye tuberculosis. In such cases it
was often that the disease was in the
non-vital parts. Sometimes one might
cut pounds of tubercular tissue away
and yet the animal might be all right.
When the bacillus got into the lungs,
the kidneys, or the liver and provoke
extensive disease, the animal promptly
developed outward symptoms.
The view held twenty years ago was
I that tuberculosis was disease that
spread rapidly, and within a short
time determined the serious illness
and death of the patient They now
know that was a wholly erroneous
view. and the truth with regard to-
tuberculosis was that Is was compar-
atively mild disease both in man and
Ianimals. The great majority of those
who contracted tuberculosis were not