A Brief Historical Sketch of the Parasite of Malaria fileA BRIEF HISTORICAL SKETCH OF THE PARASITE...

4
I

Transcript of A Brief Historical Sketch of the Parasite of Malaria fileA BRIEF HISTORICAL SKETCH OF THE PARASITE...

Page 1: A Brief Historical Sketch of the Parasite of Malaria fileA BRIEF HISTORICAL SKETCH OF THE PARASITE OF MALARIA. 1 */ By Suugn.-Major J. II. Tull Walsh. / The October issue of the Indian

Dec. 1896.] WALSH ON THE PARASITE OP MALARIA. 433

Original (JLommuniqations.

A BRIEF HISTORICAL SKETCH OF THE

PARASITE OF MALARIA. 1 */ By Suugn.-Major J. II. Tull Walsh. /

The October issue of the Indian Medical Gazette contains a paper by Surgn.-Mnjor Ronald Ross on the parasite of malaria with which I heartily agree, and I take the libert}' of sending a short historical sketch compiled from notes made when I was studying the literature of the subject some three years ago. I do not allude particularly to more recent writings such as those of Manson, Thin and others, because they only confirm what had been previously stated. As the outcome of his researches during the

3Tear 1880, Dr. Laveran communicated a short

paper to the Academie des Sciences in 1881. In this paper he recorded the results of the exam- ination of 192 cases of malarial fever, intermit- tent and remittent from the districts of Algiers O

and Tunis. He stated that he had found para- sites in the blood in 148 cases. These parasites he described as follows :?

1. Cylindrical bodies, curved in the shape of a crescent, with tapering extremities ; 0 008 mm. to 0'009 mm. long; breadth 0 003 mm. with lin- ear contour; transparent, colourless except near the centre, where there is a dark spot of pig- ment granules of a very dark led ; not possess-

ing mobility ; sometimes these bodies are oval with the pigment grains disposed in a circle; they then veiy much resemble :?

2. Round transparent bodies of an average diameter of a red blood-cell, containing pigment grains; frequently at the margin of these trans- parent spheres fine filaments may be noticed

possessing rapid movements; these filaments are often three to four times the length of the

diameter of a red blood-cell. When in a state of

repose, these filaments are not visible on account of their tenuity and their perfect transparence. The filaments become detached from the spheri- cal bodies and then move freely among the blood corpuscles.

3. Bodies of round or irregular form, trans-

parent or finely granular; from 0008 to 0010 mm. in diameter, containing pigment grainsrof rounded form and of a very dark red, sometimes

arranged regularly near the periphery, sometimes agglomerated either at the centre or at a point near the periphery.

These bodies Laveran then regarded as the cadaveric forms of the mobile parasites.

4. Spherical transparent bodies enclosing, as in (2), pigment grains; mobile or immobile and much smaller in diameter than those bodies; the smallest of these bodies is about one-sixth the diameter of a red blood-corpuscle.

These bodies, sometimes free, sometimes at-

tached to the red corpuscles, Laveran regarded as developmental forms. As regards the cases in which he failed to find any parasites, he point- ed out that the patients had undergone more or less prolonged treatment with quinine, and he concluded that the quinine cured malarial fever by destroying the parasites. The blood for ex-

amination was taken from the fingers of the

patients. The original name given b}r Laveran to the organism was Oscillaria malaria?.

In a second contribution in 1882 Laveran stated that he had, by that time, found the mal- arial parasite in 300 cases. He, morever, point- ed out that these bodies could not be found in the blood of persons suffering from other diseases. He had not found similar bodies in the malarial environment.

In 18S2 Richard submitted a paper to the Paris Academy of Sciences supporting Laveran's discoveries. He had examined numerous sick

persons at Philippeville, and, while unable to find the parasite in non-malarial cases, he found it in all true intermittent and remittent malarial

fevers. He stated that the chief site of the

parasite is the red blood-cells. Examined at the

onset of the fever,* these corpuscles were seen to contain a minute clear spot perfectly round ; as this body increased in size an organism re- sembling that previously described by Laveran appeared almost filling the blood-cell. With re-

gard to the mobile filaments and the " cadaveric

forms," Richard confirmed Laveran's observa- tions in every particular.

Following closely on these researches came contributions from Marchiafava and Celli (1883) who had observed a similar parasite, which they called Plasmodium malarias. This name is the one by which the parasite of malaria is generally known. The name Oscillaria malarice was given up by Laveran as unsuitable (Trait e., p. 209). In 18S4 Laveran published his

" Traitd des fie- vres palastres" which contained tlie results of further researches. In this work*!" he describes three kinds of bodies which may be regarded as probably developmental phases of one para- site :?

1. A c}'stic "crescent-shaped body," motion- less, colourless generally, but having about its central portion a collection of small pigment granules. These bodies change form slowly, and gradually pass into bodies of an irregularly spherical shape. The ' crescents

'

are much less

common than those next described ; sometimes

they are entirely absent from blood, otherwise rich in parasites, sometimes tliess 'crescent' bodies only are found.

2. Round small hyaline bodies sometimes I showing a double contour; differing marked!}?-

By onset cannot be meant the actual paroxysm, but a

s?rae\rkat earlier stage during the preliminary symptoms. + A translation will be found among the books issued bv tlip

New Sydenham Society, 1893. y

00

Page 2: A Brief Historical Sketch of the Parasite of Malaria fileA BRIEF HISTORICAL SKETCH OF THE PARASITE OF MALARIA. 1 */ By Suugn.-Major J. II. Tull Walsh. / The October issue of the Indian

434 INDIAN MEDICAL GAZETTE. [Deo. 1896-

in size, containing more or less pigment, some- times free in the serum ; more often in or attach- ed to the red blood-corpuscles. These bodies

possess amoeboid movements and divide by fis- sion into smaller portions.

Flagellate bodies, actively motile colourless threads sometimes free, sometimes attached to the round amoeboid bodies (2) from which they appear to develop.

3. "Cystic bodies"?Large pigmented bodies of very different and irregular shapes, probably degeneration products from the other organisms.

In 1885 Marcliiafava ami Celli recorded fur- ther observations. They found hyaline non-

pigrnented hannamcebcB which became pigmen- ted from absorbing the red colouring matter of the blood and, like Laveran, they had seen

pigmented amoeboid organisms free in the serum or inside the red blood-cells. "Crescent" forms were also seen by them but less frequent- I37 than had been noted by Laveran.

These observers appear to hold a different view to that of Laveran as to the development, believing that the 'crescent' is a final, or at

any rate later, stage of the round active 'Plas- modium.

It seems to me that the 'crescent' is most

probably an encysted form, a resting stage somewhat analogous to such as we are acquaint- ed with among the unicellular algce, e.g., Protococcus pluvialis which exists either in an

active or in a non-motile, encysted state. Other

minor details were dealt with by Marcliiafava and Celli, but to avoid prolixity I will pass on to a further communication from the same obser- vers which appeared later in the same year

(Fortsckritte, No. 24). This paper dealt with

hyaline unpigmented amcebcv which become

pigmented. These plasmodia are mobile and

split up ultimately into daughter-cells. The same year and 188G saw two contributions

from Golgi describing the "

malaria-plas- nnodium." In the cases examined he also found bodies with and without pigment; also "crescents' similar to those described by previous observers. Golgi, moreover, recorded a distinct connection between the development of the parasite and the course of quartan (amoebcv febris quartance, Golgi) and tertian (a. f. tertiance) fevers. In the former the development of the amoeboid

organism takes place within three days, and in the latter within two days in such a manner that at the end of an attack of fever the pig- mented bodies i to -J the size of a red blood-cell occupy the corpuscle and gradually increase at its expense. This condition accords with what we should expect from our clinical knowledge of the t}Tpes of malaria. The pigment is gra- dually concentrated in the centre of the Plas- modium, which finally divides into 4 to 12 smaller bodies. The fever commences in the

cycle of development about the time which is

marked by the division of the parent Plas- modium and this division is continued into and

through the febrile stage. This holds good for all varieties of plasmodium; for the quotidian as well as for the tertian, quartan and remittent varieties.* Daring the "cold stage" and also in the early part of the "hot stage" many of the plasmodia, resulting from the division above referred to, disappear from the blood of the surface and extremities of the body and seem to retire into the spleen and other organs to re-

appear as unpigmented plasmodia which, by a new cycle of development, promote another access of fever. While these changes are ffoing o o o

on in the 'Plasmodium there may be frequently seen in all types of malaria " sickle

"

or "

crescent-shaped "

bodies free in the serum. In

spite of the discoveries to which I have drawn attention Tommasi Crudeli and Schiavuggi in 1885 still held the belief that the bacillus malarial was the cause of malarial fevers and stated that Laveran, Marchiafava and others were merely describing changes in the red blood- cells which resulted from the poisonous action of this same bacillus. Baruggi and Mosso held somewhat similar opinions. Arrayed against this school we have the other which maintains the accuracy of the researches of Laveran and Marchiafava. Metchnikoff (1887) recorded the

appearance of the plasmodium malarial and noted also the division into daughter-cells. Chenzinsky found the plasmodium in Odessa, and Laveran in 1889 found the parasite in the blood of persons from Tonquin, Cochin-China, Senegambia and Madagascar. In America Coun-

cilman, Osier and others, saw and described the various forms of the plasmodium malarial. In India Vandyke Carter, Crombie, Ranking, Hehir and others have recorded the presence of the plasmodia in malarial fevers, and I found them in most of the malarial cases under my care in the European General Hospital, Calcutta. I have, however, examined many cases without

finding plasmodia; this absence in undoubted cases of malaria may have been due to previous treatment with quinine, as suggested by Laveran, or they may very probably have been over- looked. The discussion between the rival schools

may be said to have been more or less closed

by Golgi (Ziegler's Beitrdge, Bd. 4). After experi- menting on animals with pure cultures of the B. malarial of Tommasi Crudeli this writer stated as final that the bacillus has nothing to do with vxalarial fevers. In connection with this con- clusion we must also remember, as I have before mentioned, that observers in the most malarious

parts of India never met with this bacillus, while

* Marcliiafava ( " Sulle febbri, etc. ") emphsises this state

ment:?" Questa segmentcizione (sporulatione) si compie ijoco prima o in coincidenza dell' inizio dell' accesso febbrile." A translation of tlie memoir by Marcliiafava and Bignami

is advertised as one of the issues from the New Sydenham Society, 1894. <

Page 3: A Brief Historical Sketch of the Parasite of Malaria fileA BRIEF HISTORICAL SKETCH OF THE PARASITE OF MALARIA. 1 */ By Suugn.-Major J. II. Tull Walsh. / The October issue of the Indian

Dec. 1896.] WALSII ON THE PARASITE OF MALARIA. 435

the Plasmodium malarice has been found in

nearly all parts of the world in which malarial fevers occur.

The points in favour of the plasmodium malarice may be summed up briefly, from the foregoing historical sketch, as follows :?

Their very general occurrence in the blood of persons affected with malaria; their absence from the blood of persons free from malaria; the curious periodic type of malaria which may well agree with the developmental cycle de-

scribed by authors, and the certain action of

quinine on such organisms, in the light of the

experiments of Binz and Laveran, etc. I may here mention that Marchiafava and

Celli believe that they have produced paroxysms of malarial fever in persons inoculated with

blood taken from a victim to malaria; but, as Osier rightly remarks:?"In regions where ma- laria is prevalent, such experiments are not

wholly free from objection." We may therefore, I think, accept as the active

cause of malarial fevers, a microscopic amceba. My own observations lead me to agree with Laveran and other authorities who believe the

plasmodium malarice to be a parasite causing malarial fever in man. In a large number of specimens which I have examined I have

generally, though not always, been able to dis-

tinguish bodies agreeing accurately with those described,?small, colourless, free and moving plasmodia; larger spherical bodies containing pigment in the serum and in the red blood-cells, and large round "resting stage

"

or perhaps, "cadaveric stage" bodies, as also the "crescent

"

amoeba. The "crescents" I have only rarely seen, and then generally in cases of irregular, slow malarial fever or in chronic remittent cases. That I have never yet seen the "fla-

gellate threads" is probably due to the fact that

as my observations have been made in the wards for clinical purposes I have not adhered strictly to the conditions necessary for their exposure. Speaking of these

" threads" Grassi and Feletti note that in order to see them well the blood must be kept warm and care taken not to crush these delicate bodies. In blood fixed with os- mic acid, these "threads" are not seen.

Besides cases coming under my own care I was frequently permitted to examine specimens of blood taken from patients under the care of my colleagues at the Calcutta General Hospital and I would here thank Surgn.-Lt.-Coi. A. Crombie for the many opportunities he has given me for examining specimens containing the malarial plasmodia.

Speaking of Trinidad, Dr. Beavan Rake re- marks:?"Many questions arise with reference to the malarial affections of the island. It is now well-known that malarial fever is associated with a polymorphic protozoon called the Plas- modium malarice discovered by Laveran in

Algiers, and afterwards found by Marchiafava and Celli in Rome and by Councilman in Balti- more. The organisms occur in various forms in the red corpuscles or as free crescentic bodies. The intracorpuscular pigmented bodies are

specially characteristic of the acute forms of

malaria and are readily affected by quinine. The crescents occur in the more chronic varieties and often persist even while the general health is improving. Osier missed the plasmodium in only eight out of 70 cases examined by him and five of these had taken quinine, so that we may fairly conclude that it is always present in malaria. It is therefore evident that the search for the Plasmodium plays a most

important part in the diagnosis of all doubtful cases."

Osier believes that this disease is invariably associated with the plasmodia and affirms as a guide to diagnosis that as far as the intermittent forms are concerned, any case which resists

quinine is not malarial. This authority further thinks that the " crescent" forms appear

" as-

sociated with the more chronic forms of malaria or with acute cases under treatment for some time." Mannaberg considers the

" crescent" forms to be encysted syzygice formed from two to four amoeboid bodies from the red blood-corpuscles. Vincent is of opinion that we are dealing with several distinct species, and this is, I think, probable. Korolko distinguishes two species of malarial

parasite, Bamamceba febris tertiance and H. f. irregularis. Some think that the parasites of malarial fever in men and birds belong to the same genus, but according to Marchiafava and Celli this is not the case, though both may possibly belong to the same sub-class of sporozoa. The exciting cause of malaria is then an

amoeba belonging to the sporozoa or rhizopoda. It has been named by various observers, Oscillaria malarice, Coccidium malarice, Plas- modium malarice, Hcvmatozoa malarice, Ilccrna- mccba malarice, Laverania malarice, etc. Whether there are sufficient grounds for estab- lishing the genera Ilcemamceba and Laverania, of Grassi and Feletti, is not quite certain, and these observers admit that it is not possible to

distinguish between Ecemamceba (7 species) and Laverania (3 species) in the early' stages of

growth. It appears likely, however, that spe- cific differences, perhaps agreeing with the

different types of malaria, do exist and, as we should expect, local variations. Man is not by any means the only animal liable to be attacked by amoeba), and a reference to some met with in other animals will not be without interest.

Danilewsky shews that in the blood of many animals parasites are found even under appa-

rently normal conditions; these amoebce belong generally to the sporozoa. They are especially common in cold-blooded animals. It is he thinks

probable that these Hcematozoa or their germs

Page 4: A Brief Historical Sketch of the Parasite of Malaria fileA BRIEF HISTORICAL SKETCH OF THE PARASITE OF MALARIA. 1 */ By Suugn.-Major J. II. Tull Walsh. / The October issue of the Indian

436 INDIAN MEDICAL GAZETTE. [Deo. 1896.

reach the blood from the digestive tract. Try- panosoma, sanguinis belongs to the FLagellatoe and is found in the blood of frogs (Rami escu- lenta, 11. temporaria and Hijla arborea). Two

forms of Trypanosoma piscium occur in various fishes (Gyprinus carpio, G. tinea, Perca fluvia- tilis, etc.), while a cytozoon resembling Hcema- gregarina has been found in the red blood-

corpuscles of Lacerta viridis. Birds also have their blood parasite resembling somewhat the

'Plasmodium of man.