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108
FINAL REPORT OF THE ROYAL COMMISSION ON TUBERCULOSIS.
The Royal Commission appointed to inquire into the relations of human and
animal tuberculosis made its final report. The Commissioners were appointed
to inquire and report with respect to tuberculosis—
(1) Whether the disaase in animals and man is one and the same ;
(2) Whether animals and man can be reciprocally infected with it.
(3) Under what conditions if at all, the transmission of the disease
from animals to man takes place, and what are the circumstances favourable
or unfavourable to such transmission.
In answer to the first question the conclusion arrived at is that " man must
therefore be added to the list of animals notably susceptible to bovine tubercle
bacilli," and that " whether one prefers to regard bovine tuberculosis and the
cases of tuberculosis in man which are caused by the human type of bacilli as
varieties of the same disease or as independent diseases, there can be no question
that human tuberculosis is in part identical with bovine tuberculosis."
As regards the second term of the reference the report states that mammals
and men can be reciprocally infected with tuberculosis, that bovine animals
are not completely immune to the human tubercle bacillus and adult human
beings can be infected with the bovine type, even the pulmonary form of this
disease in man being sometimes caused by the bovine tubercle bacillus.
In answer to the third question, viz., under what conditions, if at all, the
transmission of tuberculosis from animals to man takes place, and what are the
circumstances favourable or unfavourable to such transmission, the report states
that, as regards human tuberculosis, " animals, domestic and other, which have
been found capable of suffering from severe generalised tuberculosis of the
human type are comparatively few," and that " probably only where the cow
or goat has received a large dose of tuberculous material derived from man does
the human tubercle bacillus escapc into the blood stream of the animal, reach
her milk sinues and become eliminated with her milk." It cannot, however,
the report goes on to say, be confidently affirmed that man is wholly free from
risk through animal food, although the degree of danger cannot at present be
determined. Turning to bovine tuberculosis, the report shows that as regards
the individual cases under observation of persons suffering from tuberculosis,
the lesions of the disease (especially pulmonary tuberculosis) when fatal have
been referable, with few exceptions, to human bacilli. On the other hand, the
report states that " there can be no doubt that a considerable proportion of the
tuberculosis affecting children is of bovine origin, and particularly that which
affects primarily the abdominal organs and the cervical glands." The report
goes on to say that "judging by our feeding experiments there would appear
to be strong presumption that as regards most animals comparatively large doses
given either singly or by frequent repetition are necessary to produce by
ingestion acute progressive generalised tuberculosis, though we have recorded
instances in which a very small dose administered but once has produced this
result. Applying a like presumption to man (and our observations on the
monkey and chimpanzee in this connection afford warrant for so doing) it may
be asked in what way are children, the members of the human family who are-