EPIDEMIOLOGICAL SOCIETY.
Mr. Grainger read a paper, of which the following is an abstract:
“On the Influence of Noxious Effluvia on the Origin and Pro-
pagation of Epidemic Diseases.—Although some diversity of opinion
prevails among medical men in reference to epidemic disease, es-
pecially on the subject of contagion, all are agreed as to the noxious
influence of overcrowding, defective ventilation, and other similar de-
fects, prevalent in populous districts. It has occurred to me, that, with-
out entering into the wide field connected with the nature and operation
of noxious effluvia in general, it might not be altogether unprofitable if
some elucidation of the facts which have fallen under my observation,
both as regards the causation of, and exemption from, epidemic disease,
were laid before the members of this Society. No one is more ready
than myself to subscribe to the doctrine so well enunciated by my friend,
Dr. Carpenter, in his valuable paper “On the Predisposing Causes of
Epidemics/’ that it is not simply the collection and tabulation of facts,
nor even mere empirical generalization, that will suflice; it is the prin-
ciples and laws springing out of them which are demanded, if sanitary
investigations are to be raised to the rank of a science. But fully
recognising this as constituting the great aim and end of all these
researches, and not forgetting the large amount of practical knowledge
acquired of late years, it yet appears to me that there is abundant room
and ample reason for elucidating evidence. Many points of prime im-
portance to the public health as to matters of fact are still in much
uncertainty. Doubts relating to agents assumed by sanitary inquirers to
be deleterious still linger in the Profession, and by no means only among
its least distinguished or influential members. The exact operation of
animal effluvia, of a cesspool atmosphere, of excessive moisture,—condi-
tions often combined in the miserable courts and alleys of our large towns,
—is by no means fully ascertained. Extended inquiiies of late years
have abundantly proved that the same deleterious agents operate as pre-
disposing causes in regard to the whole class of zymotic diseases; that
what will develope the exciting cause of fever will also develope scarla-
tina, small-pox, diarrhoea, or cholera. So certain and notorious is this
fact to those who practise among the poor, that before the outbreak of
any epidemic, knowing where the predisposing causes are rife, they can
foretell the precise localities where it will occur, nay, even name the
alley or point to the exact house that will suffer. Such considerations
have long induced me to conclude, that in regard to zymotic affections,
the predisposing are infinitely more important than what are called the
immediate or exciting causes. In regard to low fever, for example, it
is certain that its efficient cause, the materies morin, is never absent
from London and other large towns; and yet it is rarely, many would
say never, developed, unless there be superadded to it some predisposing
cause. So true is this, that we not only daily see in the metropolis and
elsewhere hundreds and thousands of persons living in the front streets
exempt from typhoid fever, while the inhabitants of the wretched courts
behind are scarcely ever free from it • but if by chance a given number
of persons are planted in the very centre of an epidemic district, but
freed from the predisposing causes of zymotic affections, they also, as a
rule, will still escape.”
“ On the Influence of Human Effluvia.—According to my observa-
tion, the most injurious of all the causes operating on the diffusion of
epidemic diseases, are the effluvia proceeding from the human body,
particularly from the lungs and skin. The special deleterious agent
consists of the effete, and, as it has been proved experimentally, highly
putrescent organic matter, mingled with the expired air. That it is,
when reintroduced into the living body, highly injurious, might be
inferred from the very fact of the careful provision made by nature for
its incessant elimination from the system. That it is small in amount
is no objection to tbe intensity of its action; for, to the physiologist it
is well known that a minute quantity of a powerful agent—the putrid
matter introduced on the point of a needle in the inspection of a dead
body, a single drop of concentrated prussic acid placed in the mouth of
an animal, is sufficient to destroy life. It is in overcrowded bedrooms,
in unventilated schools, workhouse dormitories, &c. that this effete mat-
ter taints the air, and, entering the blood, poisons the system. Although
there is a great diminution in the amount of carbonic acid in tbe air
evolved in the lungs, still the evil, quoad the development of fever,
scarlatina, cholera, and so forth, depends on the organic, not the chemical
products of respiration.” The learned author referred to some experi-
ments proving the truth of this assertion. He then continued : u It is,
however, familiar to all practitioners, that human effluvia specially ex-
hibit their poisonous influence when either multitudes of human beings
are crowded together, or where a smaller number are placed in confined
and unventilated sleeping-places. Many instances of the influence thus
exerted on all kinds of epidemic disease, have come under my notice,
but only a few illustrative examples can here be adduced. The following
case illustrates the effect of overcrowding in respect to cholera. During
the epidemic of 1849, the inmates of a reformatory establishment for
voung women suffered intensely from the pestilence, 40 out of a total
of 96 being attacked, and 15, or rather more than 15 per cent., falling
victims to the disease. Now, these poor sufferers were previously in per-
feet health; they were well fed, well clothed, and carefully attended; but
the dormitories were low and much crowded; the windows, for the sake
of seclusion, were partly closed up, thus greatly interfering with the ven-
tilation. After a careful investigation, I could detect no other cause
than this for the sudden outbreak occurring at a period when there was
little cholera in the neighborhood. As regards the influence of over-
crowding in the development of low fever, I may appeal to the experi-
ence of every medical practitioner whose duties call him much among
the poor. It matters not whether we speak of the closely packed com-
mon lodging-house, of rows of houses built back to back, of the small,
unventilated, and often single sleeping apartment of the mechanic, or of
the ill-built cottages in rural districts, with their one bed-room, over-
hanging thatch and small lattice ; wherever, either from the presence of
numbers or the absence of ventilation, you have the fetid sickening air
generated by human effluvia, there assuredly you will find fever. Al-
though observed especially among the poor, fever, as it occurs in this
country, is not especially dependent on poverty and destitution.
Want may, indeed, aggravate the evil, and actual famine, as we
unhappily saw a few years ago in Ireland, may give immense develop-
ment to typhus; but that persons well fed, living in comfort, and
strong in health, may suffer severely from low fever, is shown by a
large experience. One of the best examples, perhaps, is furnished by
the sailors belonging to the collier vessels frequenting the Thames.
These men, as a body, are in the prime of life, robust and well fed;
but as I found by examining many of these vessels, the place where
they sleep—the forecastle—is excessively small and confined, and with
this serious additional evil, that as the hatchway is usually flush with
the deck, whenever there is much sea, it becomes necessary to close the
hatchway, where the unfortunate sailors must be without any window,
as if shut up in a close box. When, too, the vessels come to London,
as only one man is required to keep watch at night, all the sailors are
crowded at the same time into their closely-packed berths. Some years
ago the attention of Mr. Busk, the distinguished surgeon of the Sea-
man’s Hospital Ship, was attracted to the large number of typhus cases
which were admitted. In 1841, they amounted to 147; in 1842, to
167. It appeared that of all the vessels in the Thames, the colliers
furnished the most fever cases. In investigating this question I could
detect no other cause than the polluted air these men must have breathed
in the confined forecastle. That there is nothing connected with a
sailor’s mode of life to expose him to typhus, is proved by the expe-
rience of well-managed vessels, and, as one among the many proofs
which might be adduced, I may mention that Mr. Clark, who has made
ten voyages to India as surgeon in Messrs. Green’s fine vessels, had
never had a single case of typhus.” The author, after referring to the
very great improvement in the health of those of the working classes
who inhabit the model lodging-houses erected in different parts of the
town by the Society for the Improvement of the Dwellings of the La-
boring Poor, and to the highly satisfactory working o*f the admirable
Act carried by the exertions of the Earl of Shaftesbury for controlling
common lodging-houses, said that his own experience of the deplorable
conditions of these abodes corroborated the statements of Capt. Hay; all
tended to show that such pestilential places were the habitats of disease,
and the cause of enormous expense to the rate-payers.—London Med.
Times and Gaz.