NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
Note on the Occurrence of a Minute Blood-Spirillum in an
Indian Rat.
BY
H. VANDYKE CARTER, M.D., LOND.,
BRIGADE SURGEON, BOMBAY.
( With Plate IV. )
The following memoranda relate to two separate subjects, either of which
may be sufficiently interesting to warrant attention. One of these fresh data is
the detection of a blood-parasite hitherto, I think, unrecognised; and the other
is the demonstration of the possibility of introducing into the circulation of a
monkey the hæmatozoon so often found amongst Indian rats—vide infra ex
-perimental series F., No. 2. In recording this last-named fact I have taken the
opportunity of mentioning other experiments and observations independently
acquired, and also of commenting on materials already acquired regarding the
pathology of the remarkable horse-disease known in India as 'surra' or 'the
relapsing fever of equines.' Some Charts and Illustrations are appended.
NOTE NO. I.—Whilst examining in August 1885 the fresh-drawn blood of
a rat (Mus decumanus) with a 1/10 inch water-immersion lens, I noticed a quick
-twirling movement amongst some of the red discs, which reminded me of the
motion produced by the human febrile blood-spirillum ( Spirochœte Obermeieri,
Cohn) and which was eventually found to be due to the presence of a similar
yet much minuter organism. In its living state this body is not easily examined,
on account of its small dimensions, its vivacity, colourlessness and translucency;
but in dried and aniline-stained preparations it becomes distinct as an extended
and uniformly slender filament of clearly spiral construction, having a length
commonly somewhat less than the diameter of a red blood-disc, but varying
from 5· to 9· μ , equivalent to about the 1/5000 to 1/3000 of an inch, and according
to its length presenting from 4 to 8 close spiral turns. The organism is exceed
-ingly slender, and both of its ends seem a little pointed; at neither end, how
-ever, could I, with an English P. and L. 1/12 inch oil-immersion detect a flagel
-lum. The structure appeared homogeneous throughout,— vide (Plate IV, figs.
I and 2). If, before staining, the dried specimen of blood be rendered translu-
cent by strong acetic acid or solution of potass, a clearer view of the organism
46
Scientific Memoirs by
may be obtained, without any more manifest alteration of its aspect than a
slight thinning.
The number of spirilla present was always moderate—2, 3, or 4 at most
being usually visible in the field at one time; but after dissolution of the
obscuring red discs a somewhat larger number may be brought into view, and
only by such method can an accurate estimate of the total be made. If only
50 organisms occur in a drop of the rat's blood, the entire number in the cir
-culation would amount to several thousands. Though sometimes I failed to
detect at once any organisms, yet, as a later search might prove successful, or a
scrutiny by the clearing method just alluded to, I was led to infer that pos
-sibly some few commonly existed in the blood. As occurs with the human
spirillum, this form showed a tendency to resort to the open serum spaces left on
coagulation; but on the other hand there was not then seen a disposition to
join or cluster in close groups, nor did the red discs seem to be especially
attractive to them. Their movements in the fresh-drawn blood were very active
and tolerably sustained, consisting of rotation round the long axis, propulsion
either forward or backward, and occasionally an energetic lateral twisting or
lashing. It seemed as if during movement a slight unwinding of the screw,
with consequent elongation, also took place. When stationary, the filaments
are extended and the spirals distinct; simple rotation may occur without any
other change in position. Owing to the varying obliquity of direction assumed,
much variety of aspect ensues; and a mere dancing dot—the tip of a verti
-cally submerged filament—may for a time be the only visible sign of its
presence.
In hermetically sealed specimens of blood, either pure or diluted with half-
-per-cent. salt solution, the spirillum may be watched at leisure for a period of
over 24 hours. Its movements become languid and more rotatory, the form
rigid, and the spirals closer set: with quiescence at the end of 12-24 hours or
more, the filaments may assume a dotted aspect, which did not change so long
as detectable, but at this time observation becomes difficult, and after repeated
efforts I was unable to trace unequivocal signs of spore-production: in the course
of 40-50 hours the organisms ceased to be visible. The temperature of the air
ranged from 78° to 85° F.
The blood for examination being obtained by puncture of the skin (at toe
or root of tail), the admixture of adventitious particles was inevitable, and,
in consequence, bacteria soon made their appearance in the sealed specimens
watched.
That the filaments under consideration are defined living organisms was
sufficiently self-evident; and under the circumstances of enquiry, they might
have been regarded as possibly either incipient monads of the usual kind, or
as a form of streptococci. Yet, on the one hand, I never perceived any trace
48 Scientific Memoirs by Medical Officers of the Army of India.
proceeding from the body: there was found serous inflammation of the pericardium and
pleuræ, pyæmic infarcts in both lungs, most on right side with consolidation; liver large,
pallid and infarcted with ova and a hydatid cyst; spleen large and pale, so the kidneys;
the intestinal canal thin-walled; Peyerian glands unchanged, no entozoa here; blood from
r. ventricle seemingly free of organisms; micrococci in the lymph and in the lung-nodules
examined: in the intestinal mucus bacteria and ova of two kinds; no monads or spirilla
seen: none of these data are peculiar.
Lastly, as to infectiveness of this spirillar blood-contamination. Soon after its cap
-ture (see the Chart) a drop of the infected blood of the rat was inoculated subcutaneously
in a healthy rat ( a) and in a healthy monkey, Macacus ( b), whose temperature and blood
were examined twice daily for six days continuously, with subsequent watching. The
result of both these trials was negative: the monkey remaining well, and the inoculated
rat only later becoming affected with gangrene of the hinder limbs (injured) such as other
non-inoculated rats were liable to: its blood was found free from organisms the day before
its death. Hence the inference that this particular form of blood-parasitism is not easily
transmissible to the same healthy species, or to another animal—the monkey—known to
be readily infected by similar inoculation of the human spirillar blood-contamination: all
the data, therefore, as they stand, concurring to indicate a difference which is not without
a certain significance.
On the lately demonstrated Blood-contamination and Infective
Disease of the Rat and of Equines in India.
BY
H. VANDYKE CARTER, M.D., LOND.,
BRIGADE SURGEON, BOMBAY.
( With Plate V. )
In July 1877 the late lamented T. R. Lewis, soon after visiting Bombay to
see the then newly-found relapsing fever organism of man—Obermeier's blood
spirillum—made the observation, also novel here, that the blood of seemingly
healthy rats often contains a ' flagellate organism' which at first sight was not
dissimilar to a spirillum. Towards the close of 1880 Dr. Griffith Evans, A.V.D.,
whilst investigating in the Punjab frontier the equine disease known as 'surra'
(a wasting disorder), made the further discovery that the blood of affected
horses contained a specific parasite, which Dr. Lewis then identified as being
very closely allied to the flagellated parasite of the rat; and by experiment
Dr. Evans showed that the 'surra' contamination and disease were both com-
-municable through inoculation to healthy horses and also to the dog. In
January 1885, Mr. J. H. Steel, A.V.D., when investigating a hitherto unrecog
-nised disease amongst the transport mules in British Burma, found it to be the
s ame as t he ' s ur r a' of t he N. - W. Pr ovi nces , and was f ur t her l ed t o r egar d t he
specific organism as a ' spirilloid' and the malady as a fever of relapsing type.
Mr. Steel also showed that the monkey was susceptible of this infection, and
at Dr. Evans' suggestion having applied to me for some technical information,
he was good enough to send from Burma to Bombay several specimens of the
tainted blood of mule, dog, and monkey, through means of which, by direct com
-parison, I too was enabled to identify the hæmatozoon of 'surra' with that of
healthy-looking rats; and the subject being an interesting one, I continued to
pursue it at leisure during 1885. My notes at that time were generally confir
-mative of prior morphological observations, including Lewis' latest published
memorandum in the Quarterly Journal of Microscopical Science, July 1884 (which
I had not then seen in India); and they also contain figures anticipating some
quite recently given by Dr. E. M. Crookshank (Journal of the R. Microscopical
Society, under date November 1886), who, in England, having examined Dr.
Evans' specimens of the equine 'surra' blood, and of the tainted rat's blood
procured in London, considers the hæmatozoon in both to be identical in character,
H
and in more detail to belong to the genus Trichomonas of Leukart. It there
-fore appears that not only is the morbid equine hæmatozoon of the Punjab
the same as that of Burma (Poona in the Deccan may now be added according
to Mr. Steel), but also that both of them correspond to the hæmatozoon of rats
at large in Calcutta and Bombay, and, moreover, to a like organism common in
London rats. I will only add here that in India the camel may spontaneously
suffer along with horses and mules; also that in Europe, with rats, the hamster
may be thus contaminated, and certain fishes (the mud-fish and carp) with
organisms not unlike.
Data from Bombay. —These include observations and experiments made
with fresh material derived from rodents ( a ), and a short account of Mr. Steel's
equine and other specimens from Burma ( b ).
( a) Observations on rat's blood .—Animals obtained were chiefly of the
species Mus decumanus and M. rattus (?), the small brown or grey rat being of
-tenest found infected. A few examples examined of M. bandicottus and of Sorex
sp. (also of mice) gave negative results. Males were tire most numerous;
in pregnant females the fœtus was not implicated: the animals were active, non
-febrile, and, barring injuries incidental to capture, all seemed alike healthy, so
that one could not surely guess beforehand the state of their blood. Material
for scrutiny was taken from root of tail or from the paws by puncture after
cleaning: only a small-sized drop could be had daily, and the admixture of some
impurities was unavoidable by this method. For inoculation and peritoneal injec
-tions blood from the heart was used. A magnifying power of 300 linear com-
-monly sufficed, but the higher powers were used and repeated scrutinies made
when doubt existed; on such rarer occasions I have detected the Trichomonas
in sealed specimens only on later trials, the number present being then extremely
few. The animals were kept usually apart and fed on wheaten bread, rice, and
water ad libitum: most were killed after examination, others preserved might
survive for weeks or over a month, but most of them died at a much earlier period,
apparently from the effects of confinement or possibly as the result of injuries
received. The temperature was taken twice or thrice daily per rectum, and
usually in control-animals as well as those under experiment. From 99°F.
A.M. to 101° P.M. (37·3°—38·4°C.) seemed to be the common range under con
-ditions stated; but degrees somewhat higher and lower were occasionally noted,
attributable perhaps to excitement or exhaustion.
Of 60 rats caught in February, 9 (or 15 per cent.) showed the Trichomonas;
their source was various rooms in a large hotel, and the infected commonly
came in groups of two or three from one room, which might be on an upper floor.
Of 150 rats caught in August to December, only 16 (barely 10 per cent.) were found
infected; their source was, however, more varied, namely, from dwellings or ware
-houses in several parts of the native town, and as only individuals were
Medical Officers of the Army of India. 5 1
often brought the evidence of an endemic source of infection was here less ap-
parent, and valid inference regarding a possible seasonal influence could not be
made. At the hotel alluded to the rats had finally become too wary to enter
the traps, but some infected animals from the kitchens were caught together.
Inclusive proportion showing the hæmatozoon nearly 12 per cent., which is less
than one-half of the percentage found in Calcutta and London.
A scrutiny of selected bi-daily records for 65 days did not reveal any
pronounced or constant differences in the rectal temperature of infected rats
as compared with the non-infected. And when it happened that the monads
disappeared suddenly from the blood, there was never noted any striking cor-
responding change of temperature; indeed, as the Charts I have show, no
change at all might ensue surpassing the normal range so far as known. Pos-
sibly under greater stringency some relationship of body-heat and this para-
sitism of the blood may be revealed, but none such has yet come to light.
I also failed to perceive any marked difference in the general state of the
two sets of animals compared; both being equally liable to inconveniences or
incidental hurt, either flourished or did not thrive in similar degree, for periods
of several days or some weeks. If these data were not very numerous or
rigidly exact, it was still clearly ascertained that the aspect of complete health
was compatible with the presence of numerous flagellate organisms in the cir-
culation. There was no evidence of a contagious influence.
A common lesion amongst animals kept was atrophy or necrosis of the
tail, then usually the feet became swollen, and finally there were signs of para-
plegia and extreme debility. No animal kept in confinement lived longer than
six weeks, and the majority not more than a fortnight; death usually superven-
ing gradually as if from exhaustion, and a terminal febrile state never being wit-
nessed. Mere confinement seemed prejudicial; and even if the diet were un-
suitable, the signs of actual starvation were not noted. Occasionally death
was sudden and unsuspected, during the night, and as if spontaneous. All these
events were common to infected and non-infected animals, about equally.
Fifteen special autopsies were made, of which 9 of rats showing the
hæmatozoon, and in none of them did I see any peculiar coarse lesion of blood,
or of viscera or tissues of the trunk. The brain was not examined. Microscopi-
cally, the only changes noted was an increase of leucocytes; the spleen elements
seemed normal. Some details are the following, which may be useful to future
observers : —
No. I.—A large and active rat with swarms of monads in the blood: strangled and
forthwith opened. The blood reddens and quickly sets; no marked changes anywhere
visible: liver-tissue healthy and free from ova or hydatid. No intestinal entozoa, some
hyperæmia of mucosa in ileum and clear mucus near the ileocæcal valve: the mucus of
duodenum and ileum free from monads. Cæcum filled with greenish soft pulp containing
H 2
Medical Officers of the Army of India.
53
to the action of acetic acid or liquor potassæ; all the filaments present, by this
method, becoming visible and readily counted. Often the number present in
the field seems equal to or greater than that of the leucocytes, and occasional-
ly comparable to a percentage of the red discs themselves; such a swarming
may, however, be illusive, yet if the parasites were only 1/500 the number of red discs,
their total in the circulation would amount to some millions. As to the movements
exhibited, whilst it is possible such may be exaggerated outside the body under
conditions abnormal and likely to prove irritative, still it may be assumed that
during their stay within the blood-vessels, these organisms maintain a degree
of activity curious to contemplate. As seen in the freshest blood, their move-
ments are so rapid as to be followed with difficulty by the eye, certain optical im-
pediments concurring thereto; yet evidently the chief one is that of progression
more or less direct, and accompanied by a lateral lashing or sometimes an ap-
parent rotation. Progression may doubtless be either backward or forward, and
misled by the idea of the thicker end being the head of the organism, I (like Lewis)
gained the impression that it commonly advanced; yet it is certain that when
more tranquilly performed, progression is really with the flagellate extremity in
front, as is usual in the other infusorial monads: this datum is important.
In the fresh state, the substance of these organisms appeared under the
higher powers to be homogeneous and translucent; yet, as described below, there
presently appeared one or more bright spots in the thicker part. The very
delicate lateral membrane became visible only in my osmic acid and stained
specimens, and these serve to conform Dr. Crookshank's later observations to
a considerable extent (see the figures in Plate V.) Aniline staining, which has
proved so serviceable in Bacterial researches, did not seem to me equally trust-
worthy here, on account of the inconstant degree and site of colouring which it
imparted; at least by this means I did not become assured of the presence of
internal organs, or of definite series of reproductive particles. Mr. Steel's
specimens from Rangoon however, when stained with methyl-violet, showed
distinct appearances of immature organisms or rudiments, such as I find Dr.
Crookshank has also detected and figured in the rat's blood: they merit further
attention.
The next topic I would notice is the changes exhibited by these hæmotozoa
in blood hermetically sealed, at rest and at a temperature of 70°—80°F. in the
shade. Numerous experiments were made in February and in September 1885,
and at the time I was not aware that Lewis had made similar observations as
recorded in his second Memoir: subsequently Dr. Crookshank has also alluded
to this subject. My own results may be illustrated by the following extracts
from Note-books preserved:—
February. —A minute clot of infected rat's blood was covered with a drop of .75 per
cent. solution of common salt, and examined at intervals with 1/10 inch water immersion lens.
Medical Officers of the Army of India.
59
For valid inference it was obviously needful to ascertain the sameness
of the things under comparison. This might be done either morphologically
or biologically; and one striking feature of the present instance consists in its
offering an apparent discrepancy in these two respects, which, so far as I know,
is unique in the annals of experimental pathology.
First, as to the morphology of the hæmatozoon. Judging from description,
there can be no doubt that the organism found in Bombay is identical
with that detected by Lewis in Bengal; such inference being confirmed by the
micro-photographs appended to the Calcutta Memoir of 1879 and the remarks
and drawings in Dr. Lewis' "Further Observations," London, 1884. Here I
may note also the very close similarity (at least) of the Indian hæmatozoon
with that of the German "hamster" described by Wittick and illustrated
by excellent photographs, with a comment in Koch's well-known article
Mittheill. a. d. Konigl. Gesund. amt. Band. I—Berlin, 1881. And not less
evident is the identity therewith of the London flagellate protozoa more
recently described and illustrated by Dr. E. M. Crookshank 1. c. 1886. I
am not acquainted with other details ( if any ) published in India or elsewhere
respecting the seemingly non-pathogenic hæmatozoon of rodents; but the
above concurrent testimony is sufficient to establish the wide prevalence, as
well as identity, of this species of blood-parasitism.
Adverting, next, to the pathogenous equine-form, my observations date
from the beginning of 1885, on the receipt from Rangoon of Mr. Steel's dried
specimens of blood of the naturally diseased mule, and the artificially infected
mule, dog and monkey, taken at different periods of illness; the preparations
arrived at Bombay in fair condition and were successfully stained with methy-
lene blue, methyl-violet, and fuchsine. After careful and repeated scrutinies,
I arrived at the conviction that no essential difference in aspect existed be-
tween the organisms present in the natural and the acquired disease, nor be-
tween either of these sets and the common rat-infection. Learning subse-
quently that Dr. Lewis had arrived at a similar conclusion, as regards the
hæmatozoon of Calcutta rats and of the Punjab "surra" mule disease, as
well as of a dog infected therefrom, my notes were allowed to stand over. Dr.
Crookshank has since demonstrated that the organism from the Punjab
entirely corresponds in aspect to that found in London rats. Lastly, Mr. Steel,
having become well acquainted with the Bombay organism in the fresh state, is
also of opinion that their aspect is identical with that of the parasites in fresh
"surra" blood as seen in Burma. More recently still the equine malady and its hæ-
matozoon have been detected by the same observer at Poona in the Deccan; so
that India is the seat of a widespread and very serious equine-disease, having for
one of its characteristics a blood-contamination seemingly identical with one
largely prevalent amongst common rodents of the country. Other countries
may be in the same predicament.
J 2