NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
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village that any and every case of illness, alike chronic and
acute, will be brought out and exhibited to one under that
name. Nor is this unnatural. Even the most highly-civilised
natives of Europe can hardly be trusted to diagnose their
own diseases ; and I would submit that if, in all cases, as has
been done in this instance, we left the diagnosis to the patient,
there are few diseases in which we should not be in equal
confusion, and that, for example, in India at least we should
draw no distinction between small-pox, measles, and varicella ;
for it is notorious that, in most parts of India, natives return all
three as small-pox : yet either of the three might be the cause
of a widely-spread epidemic, and to argue that an epidemic of
measles must necessarily be one of small-pox, because the latter
disease had always been common in the affected district, and
the general populace saw 110 difference between them, would be
obviously fallacious, and none the less so, because it would
be necessarily easy to find plenty of cases of true small-pox to
support one's contention.
To account, however, for a malady which causes a
mortality so rapidly increasing, so severe, and so different
from our previous experience of the diseases of the country,
we must seek some newly-introduced cause : some disease
which has not been always endemic, and not a malady like
malaria, which has always been rife in Assam, and which
depends on conditions which have remained entirely un-
changed. We are, it is true, still much in the dark as to the
exact causation of malaria, but, if this enormous increase
of sickness be due to it, we ought to be well on our way to
a certainty, as to some at least of its effective causes, for
these causes should be in prominent action in the affected
villages to an extent seldom before realised. Nothing of the
sort, however, can be found. I am aware that the disturbance
of the drainage lines of the country by newly-constructed em-
banked roads, and also the extension of forest reserves, have
each been suggested as the possible cause of the assumed
intensification of malaria ; but neither suggestion will bear
even the most casual examination.
To begin with, the distribution of the malady bears no
relation whatever either to roads or reserves. Further, if
an embanked road, by stopping the outflow of water, render
the ground above it damper, it is perfectly clear that it
must necessarily render that below it drier. Water cannot
flow in more than one direction. If such a road be placed
in the line of the gradient of the land, it can exert no
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influence in either direction. If, however, it be placed more
or less parallel to the lines of contour, it must render the
contours above it damper and those below it drier. Most
of the great roads do, in point of fact, run parallel with the
contouring of the country, or, in other words, between the
hills and the river, and must, in so far, tend to render the
land between the hills and the road somewhat damper than
before their construction. I doubt, however, if they are
adequate to produce any very appreciable effect, for they seem
very fairly provided with openings, and bhils, and other col-
lections of standing water seem just as common 011 the one
side as the other ; moreover, if they really did interfere much
with drainage, it is perfectly certain that they would not
stand long.
However, assuming them even to have such an effect,
and so to enhance the malariousness of the country, on one
side of the road, it is perfectly clear that the general health
ought to be proportionally bettered on the other side, but
no one has even suggested that this has taken place.
In a country like Assam, where so large a proportion
of the total area is virgin forest, I have never been able to
understand how any one could soberly suggest that the
petty amount of afforestation effected by man can have any
influence on disease. It seems like accounting for the grimi-
ness of Newcastle by the importation of a few baskets of
charcoal.
In the absence, then, of any intelligible cause for intensi-
fication of the well-known malariousness of the affected districts,
it seems as great a mistake to attach any importance, in the
production of the increased mortality, to such cases of mala-
rial cachexia as one meets with, as to the cases of dysen-
tery, pneumonia, and spinal caries.
Personally, I have not found cases of uncomplicated
malarial cachexia at all commoner than I have in certain parts,
for example, of the Central Provinces and Punjab. What I
have, however, found is that, wherever a village is seriously
affected with kála-azár, the larger proportion of serious illness
will be found to consist of cases of anchylostomiasis. That a
very large proportion of the cases will be found to be
complicated with enlargement of the spleen is quite beside
the question, for, as we have seen, this condition nearly as
often complicates apparent health. Malaria doubtless accounts
now for as much sickness and death as it always has, and
that, we well know, is no small amount ; but it is entirely
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inadequate to serve as the efficient cause of the terrible death-
rate of kála-azár-sfaicken villages, and the true cause of this will
be found to be neither more nor less than anchylostomiasis.
Of course, it is perfectly intelligible that a man brought low
by anchylostomiasis should more readily fall a victim to
malarial influences. In the closely-analogous case of famine,
we know this to be the case, but it is to shortness of food, and
not to malaria, that we ascribe the high death-rate of periods
of famine, in spite of the fact that many poor, half-starved
wretches might have survived but for attacks of fever and
enlargement of the spleen. Conversely, a. man, already the
subject of malarial cachexia, will die much more rapidly from
anchylostomiasis than an originally healthy subject.
As will be seen, I am far from asserting that any and
every case that will be produced as kála-azár is necessarily
anchylostomiasis, or that cases of malarial cachexia are
otherwise than very common, for such · cases are very common
now, always have been, and it will be long ere they cease
to be so. All I wish to convey is that the increased morta-
lity is due to the anchylostomiasis, and to no other cause, and
hence the answer to the question propounded at the com-
mencement of the section must be that if we take kála-azár
to be anything brought as such, kala-azar may be anything,
but that if we confine ourself to the cause of the present
pestilence, the reply is that it is anchylostomiasis.
If, as it is to be sincerely hoped will not be the case, the term
kála-azár be retained at all, it should, I think, be confined to the
cause of increased mortality, which has given rise to the term.
The preferable course, however, will be to classify our cases
under the headings of ordinary medical nomenclature, and
to avoid entirely the use of such misleading terms as kala-
azár and beri-beri.
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VI.—THE LIFE HISTORY OF THE PARASITE.
The immense numbers of ova which, are to be found in
the dejecta of patients suffering from anchylostomiasis has
already been adverted to. We must now attempt to follow
what happens to these after they have been deposited on the
ground.
If we watch a deposit, we shall find that, in warm, damp
weather, by the next day there will be little or no offence, and
little to be seen of the fæscal mass. In its place we shall find
the ground turned up into minute heaps of granules. This has
been mainly effected by the agency of several species of beetles
which feed on the excrement, and carry much of it down into
their burrows.
In spite, however, of the destruction of the greater part of
the mass by these little animals, if we examine the soil, the
next day, i.e., two, days after deposition, we shall find it absolutely
swarming with minute nematode embryos. In three or four
days, the place where the faeces were deposited will be difficult
to make out, and by the end of ten days no trace of its presence
will remain to the naked eye, but the microscope will reveal
the presence of the embryos, in even increased numbers. During
the cold season, when many of the species, which thus act as
scavengers, are sluggish, or perhaps hybernating, the deposit
will remain longer on the ground, and its traces will be discern-
ible for a long time, but the ultimate result, though deferred,
will be the same.
As will afterwards appear, when we come to discuss the
methods of infection, this rapid disappearance of the offensive
matter, and the persistence of the embryos 011 the site it
occupied, has an important bearing on the transmission of the
disease. In the case of the small pits, which have been already
mentioned, where there is a considerable accumulation of fæcal
matter in one place, the efforts of .the scavenger beetles are in-
sufficient, indeed they will not be found except at the edges of
such accumulations, and hence in this instance the greater part
of the fæcal matter remains at the disposal of the nematodes,
which are thus enabled to flourish even more vigorously than
in the case of isolated deposits.
For purposes of investigation, however, it is better to insti-
tute a regular cultivation, but nothing but fæcal matter will
serve for the proper nourishment and development of the
worms, so that the course of events as seen in nature must be
followed as closely as possible.
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I have transferred embryos to the ordinary nutritive
media, used in bacteriological investigation, to meat juice and
other fluids that, it appeared, might offer a suitable and in-
offensive cultivating material, but, though the embryos often
contrived to live in these for several days, all growth and
development was at once stopped. From the circumstance
that the intestinal contents of the embryos change to a purple
hue under the action of Pettenkofer's test, it may be consi-
dered probable that the worms find their nourishment mainly
in the biliary matter found in the fæces, and, as far as my
experiments go, they show that it is quite useless attempting
to observe the development of the worms except they be
provided with fascal nutriment.
However, by utilizing the deodorizing powers of earth,
we may obtain cultivations of the worms, which if not abso-
lutely free from offence can yet be dealt with without any
great amount of personal annoyance. After trying a great
many plans, I find the method most favourable to the develop-
ment of the worms is to place the suspected fæces in a lightly-
covered vessel, such as a gamlah tied over with muslin, for a
day or two, and then to add sufficient water to render the
mass quite fluid.
A shallow crystallizing glass is then about half filled
with clean white sand, which should not be too fine, and a suffi-
ciency of the diluted fæcal matter is poured over this, without
touching the sides, so as to thoroughly wet the sand without
causing obvious pools on the surface ; and, finally, the whole is
covered with a piece of clean window glass. From time
to time (every day or two) the glass cover must be raised so
as to renew the air within the chamber, as I find that the
worms can only develop in the presence of a free supply of
oxygen. Freshly-collected fæces may be employed in the
same way, but I am inclined to think, as a result of many
experiments, that the development is rendered more sure by
the ova being allowed to remain from 24 to 48 hours in their
natural habitat.
A certain amount of dampness is important in ensuring
the best result, and the degree of this may be best expressed
by stating that the grains of wet sand should still hold a
certain amount of air entangled amongst them. No doubt,
this is connected with the necessity the worms, in common
with other animals, have of obtaining a free supply of oxygen.
The length of time taken in hatching out varies greatly with
the temperature of the air. At what degree development
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altogether stops I am unable to state, as, owing to the impos-
sibility of obtaining ice, I was unable to institute any experi-
ments on the point. As far, however, as Assam is concerned
this is unimportant, as the temperature here, even in the cold
weather, never falls sufficiently low to do more than retard the
hatching process.
In December, at Gauháti, the temperature in my labora-
tory ranging a little above 60°F. during the day, and falling
to about 54° at night, the embryos do not commence to
hatch out until the fifth day, and then only a very small
number, the greater proportion not appearing until the sixth
day. On. the other hand, in an observation made at Dhubri
late in March, the temperature being about 84° in the
room where I was working, the embryos hatched out the
day after the deposition of the excrement ; while in Shillong,
at an intermediate temperature of about 70°, they usually
did not appear till the third or fourth day. I made some
attempts at ascertaining the effects of a higher temperature,
but my constant temperature apparatus proved a failure, and
the experiments that were attempted in it were necessarily
inconclusive. They showed, however, that the embryos can
live for a considerable time at a temperature of 120° P.
The ova, as met with in the fseces, have a very charac-
teristic appearance, and once seen cannot well be mistaken
for anything else. As the average of a large number of
micrometrie observations, I find they measure 1/420 inch in length
by 1/630 inch in breadth. As far as can be made out from the
very rough figure in Dr. Kinsey's pamphlet, this coincides
pretty closely with Perroncito's measurements, but his figure,
to'judge from the varying size of the ova represented, can only
be a free-hand production, and therefore cannot be taken as
exact. I can find no statement as to the measurements of
the ova in the papers of either Dr. Adolph Lutz or Dr.
Schulthess.
In the last edition of Dr. Bristowe's " Theory and Practice
of Medicine," the measurements are stated as 1/540 inch by 1/1000
inch. The statement is of course, not original, as the author
could have had no opportunity of personal observation, and
the authority for it is not given, but if it be based on correct
observations, it must refer to a distinct species from that
observed in Assam, as the measurements of the ova of any
one species vary within such narrow limits only, that it would
be impossible to find any two ova differing by as much as
1/420 inch and 1/540 inch, so that either the ova referred to belong
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to different species, or some mistake has been made by the
authority from which Dr. Bristowe took his description.
The exact measurement, however, is of great importance
in the diagnoses of c'ases by microscopical examination of the
fasces, especially when it is attempted for the first time, before
one has become familiar with the general appearance of the
ova ; and hence this statement in Bristowe gave me a great deal
of trouble in the early stage of the investigation, and, mistrust-
ing the exactness of my stage micrometer, I sent for a new
one, but both instruments give the same readings, so that the
above measurement may be accepted as exact.
In fresh fæces the ova are usually 2-4 segmented, but I
have often met with unsegmented ova. The yelk is of a
greyish colour, and is separated from the shell by a compara-
tively wide zone of perfectly clear, transparent fluid. As this
fluid and the egg-shell are alike quite white, it is by this
character alone perfectly distinguished from the ova of Ascaris
lumbricoides, which are yellow, and from those of Triclwce-
phalus dispar, which are deep red brown. This clear zone is
usually wider at the poles than elsewhere, and is not found
to the same extent in airy other human parasite. Another
peculiarity is that the egg has a tendency to a cylindrical
form ; in other words, its outline is not truly elliptical, but has
its longer sides somewhat flattened.
The only human parasite with whose eggs it can possibly
be confounded is the Oxyuris vermicularis, but this latter is
somewhat smaller, being only 1/490 inch in length, its outline is
unsymmetrical, being flattened on one side only, and, lastly, it
always contains a well-advanced embiyo. Now the most
advanced Dochmius ova which can be found in fresh freces
are in the morula stage of development, so that the mistake
could only arise in examining faeces that have been passed
some time, though, as we have seen, in hot weather 18 or 20
hours would be sufficient.
After reaching the morula stage, the first indication of
the embryo appears as a slight groove, rather to one side of
the pole of the morula. This groove deepens until the em-
bryo can clearly be made out as a tadpole-shaped body bent
on itself. The embryo now rapidly increases in length, at
the expense of the thickness of the larger end, until a distinct-
ly worm-like body results. Before this process is completed
even, slow movements begin to be observable in the mass,
until at length the embiyonic worm can be seen in constant
motion coiling itself about in the egg with such rapidity that
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it is very difficult to obtain a correct drawing. The movements
become more and more violent, the creature appearing to
struggle to straighten itself out, till at last the shell ruptures,
as a rule, a little to one side of one of its poles. The little
worm soon wriggles itself free from the empty shell, and at
once begins to move about actively in the fluid in which it
finds itself.
Immediately after emerging from the egg, the embryo
measures 0.085" in length by 0.005" in diameter. It tapers a
little towards the head, which is rather blunt, and terminates
in a finely-pointed tail. The whole length is marked with fine
transverse striations as close as those of muscle fibre. Under
a high power, the intestinal canal can be clearly made
out, but is not as prominent an object as it becomes a few hours
later, when its endothelial cells have become plumped out with
granular matter.
The commencement of the intestine proper is about one-
fifth of the entire body length from the oval end of the body.
Immediately in front of this is a small chitinous bulb, which
is armed with certain chitinous ridges, so disposed as to
appear like the mouth of a leech, when seen in optical section.
When first escaped from the egg, this bulb is in a continuous
state of pulsation, its strokes being about 60 per minute,
but not absolutely regular, sometime pausing for a while. It
is no doubt by this means that the large supply of nourish-
ment required for its growth is drawn into the body. After
an hour or so, these pulsations become slower, and finally
cease. In front of the bulb, the oesophagus can be traced as a
faint outline, broadening somewhat at about half its length,
and extending to the mouth. The little animal grows at first
with extreme rapidity. Within the next 48 hours, at an
average temperature of 70°, they have increased to three times
their original length. During this time, they have undergone
several ecdyses, but the exact number of changes is difficult
to state, as it is impossible to keep any individual worm con-
tinuously under observation. Repeated experiments have con-
vinced me that observation of these embryos, under laborat-
ing conditions, are quite valueless. The nature of the medium
in which they will alone nourish quite precludes microscopi-
cal observation, and, in water, development is at once modified
and soon arrested. I have made many attempts to induce
them to grow in transparent media, but quite fruitlessly. In.
nutrient beef jelly, such as is used for bacteriological work,
whether acid, neutral or alkaline, they soon die, whether it
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be allowed to solidify or kept fluid by heat or dilution. They
live longer, but will not flourish, in urine, and the nearest
approach to success was obtained by mixing fæcal matter with
water, and filtering through nainsook, whereby a fluid is ob-
tained which, in thin layers, is still clear enough for micros-
copical observations ; but even in this I have quite failed to
observe continuously, from birth to the adult rhabditis stage,
to be described below, any individual embryo.
It is no doubt owing to too great trust in observation
conducted under purely laboratory conditions, that the des-
cription of the life history of the worm given in Dr. Adolph
Lutz's paper is full of fallacies. As those who have read that
otherwise very able paper will remember, a great feature is
made of what he terms the encapsuling and calcification of the
embryonic parasites. I can emphatically assert that in their
life history there is no such phase, under any conditions what-
soever ; and that what has been so described is not life, but
death history, in other words, they are but the changes that
occur in dead worms when left in water. I have kept dead
embryos which presented all the changes figured by Lutz
under observation for long periods, and I have never witnessed
the least sign of returning life ; further I have followed the
further change of decomposition into mere granular matter.
The only way to successfully observe the normal life history
of the parasite is to make a large cultivation and remove small
specimens at frequent intervals for microscopical examination
in water. It is here that the use of coarse sand as a basis
proves so useful, as the sand entirely does away with the tena-
ciousness of the original material, and a specimen removed
to a glass tray, and played upon by a jet of water, falls
to pieces, and is ready for observation at once. It may
be well, before proceeding further, to describe more
minutely the process employed in examining the cultivations.
The best size of tray is about 3 inches by 2 inches, internal
measurement, and about 1/3 inch deep. Such tray can easily be
made by any one as follows :—
Cut a strip of window glass 1/3 inch wide, and as thick as
can be obtained. Out off it two pieces, each 3 inches, and two
pieces 2 inches long. Cut also, from a thinner piece of glass, as
free as may be from flaws, a plate, 2½ in. × 3½ in. Now make one
of the long strips hot in a spirit lamp, and smear one edge with
shellac, or, better, a mixture of equal parts shellac, yellow bees-
wax, and resin : now heat one of the long sides of the larger
plate, and then apply the cemented strip, so that it is fixed