J R Army Med Corps: first published as 10.1136/jramc-22-02-03 on 1 February 1914. Downloaded from
152
MORPHOLOGY OF VARIOUS STRAINS OF THE TRYPANOSOME CAUSING DISEASE IN MAN IN NYASALAND-'l'HE WILD GAME STRAIN.1
By SURGEON· GENERAL SIR DAVID BRUCE, C.B., F.R.S.; MAJORS DAVID HARVEY AND A. E. HAMERTON, D.S.O., RA.M.C.; AND LADY BRUCE, R.RC. INTRODUCTION. TRYPANOSOMES of this species, isolated from five antelope, are here described and compared with the human strains which formed the subject of a previous paper.2 The wild game strains were isolated by injecting blood of antelope into susceptible animals. The blood was, as a rule, injected into a healthy goat, monkey and
dog, and from these othe~ animals were inoculated. Protected by copyright. Trypanosomes from the following species were studied: Reed buck, waterbuck, oribi, and hartebeeste. In these experiments, with the exception of the oribi, the three inoculated animals became infected. In the case of the oribi the blood was inoculated into a monkey and a dog, no goat being available, and the monkey alone took the disease.
(1) MORPHOLOGY OF STRAIN I, REEDBUCK. The following table gives the average length of this trypanosome
as found in the rat, 500 trypanosomes in all, and also the length http://militaryhealth.bmj.com/ of the longest and shortest :-
TABLE I.-MEASUREMENTS OF THE LENGTH OF THE TRYPANOSOME OF STRAIN I, REEDBucK.
In microns
Date Method of fixing Method of staining Average Maximum I Minimum length I length length Giemsa 1912 . I Osmic acid I 21'7 I 34'0 16'0 on September 27, 2021 by guest.
I Reprinted from the Proceedings of the Royal Society, B., vol. Ixxxvi. 2 JOURNAL OF THE ROYAL ARMY MEDICAL CORPS, vo!. xxi, p. 421. J R Army Med Corps: first published as 10.1136/jramc-22-02-03 on 1 February 1914. Downloaded from
D. Bruce, D. Harvey, A. E. Hamerton and Lady Bruce 153
TABLE n,-DISTRIBUTION IN RESPECT TO LENGTH OF 500 INDIVIDUALS OF THE TRYPANOSOME OF STRAIN I, REEDBUCK,
In microns
16 17 18 19 20 21 22 23 24 ------Total .. , , .. ... 5 30 57 90 81 53 27 17 16 Percentages ...... 1'0 6'0 11'4 18'0 16'2 10'6 5'4 3'4 3'2
In microns
26 27 28 29 30 31 32 33 34 Total ...... t 18" 23 18 25 18 9 8 2 2 1 Percentages ...... 3'6 4'6 3'6 5'0 3'6 1'8 1'6 0'4 0'4 0'2 Protected by copyright.
CHART 1.-Curve representing the Distribution, by Percentages, in respect to Length, of 500 Individuals of the Trypanosome of Strain I, Reedbuck, taken on nine con- secutive days from Rat 847. .
Microns 013 1415 16 1718 19 202/ 12 2~ 24 25 26 27 26 29 ~o 3/ tl2 33 34 3$ 36 137 SIl 19 18 ~ 17 http://militaryhealth.bmj.com/ 16 11 1\ IS J, 14 rn IS (11/2- ~~/I .1 +> /0 .i <: <1)9 \ Uc'I ~
154 Morphology of Yarious Strains of the Trypanosome
TABLE IlL-PERCENTAGES OF POSTERIOR-NUCLEAR FORMS FOUND AMONG THE SHORT AND STUMPY VARIETIES OF THE TRYPANOSOME OF STRAIN I, REEDBUCK.
Percentage among short Date Experiment No. Animal I and stumpy forms
----191-2---______1------
July 17 ...... 847 Rat I1 4. 20 847' I 2 22 8<17 I 2 " 23 847" 4 24 847 ,9 ~ W ID " 26 847 19 " 27 847 22 ~ M7 4
Average
(2) MORPHOLOGY OF STRAIN rI, WATERBUCK. The following table gives the average length of this trypanosome Protected by copyright. as found in the rat, 500 trypanosomes in all, and also the length of the longest and shortest :-
TABLE IV.-MEASURElI1ENTS OF THE LENGTH OF THE TRYPANOSOME OF STRAIN Il, WATERBUCK.
In microns Date Method of fixing Method of staining Average Maximum Minimum length I length I length
1912 Osmic acid Giemsa 23'5 33'0 16'0
I I I http://militaryhealth.bmj.com/
TABLE V.-DISTRIBUTION IN RESPECT TO LENGTH OF 500 INDIVIDUALS OF THE TRYPANOSOME OF STRAIN Il, WATERBUCK.
In microns I 18 21 22 23 24 ------_16_1_17_ -----19 I 20 Total...... 8 26 59 74 58 58 44 Percentages ...... 0'21 I 0'42 1'6 5'2 111'8 14'8 11'6 11'6 8'8
In microns on September 27, 2021 by guest.
25 I 26 27 28 29 30 31 32 33 ------Total...... 27 I 34 33 26 17 19 9 3 2 Percentages ...... 5'4 6'8 6'6 5'2 3'4 3'8 1'8 0'6 0'4 I J R Army Med Corps: first published as 10.1136/jramc-22-02-03 on 1 February 1914. Downloaded from
D. Bruce, D. Harvey, A. E. Hamerton and Lady Bn),ce 155
CHART 2.-0urve representing the Distribution, by Percentages, in respect to Length, of 500 Individuals of the Trypanosome of Strain II, Waterbuck, taken 'on nine consecutive days from Ritt 1,220.
Microns 13 14- 15 16 17 18 W 2021 Zz 23 U 2526 27 %8 29 .so 31 32 83 34 35 36 37 38
16 15 .", 14- 13 12 , I ~ T 11- t"'\ ctlll I ·~r 1\ rd9 , 0-I-- ~B \ ~'T J"" )...6 I "'\ TABI,E Vr.-PERCENTAGES OF POSTERIOR· NUCLEAR FORMS FOUND AMONG THE SHORT AND STUMPY VARIETIES OF THE TRYPANOSOME OF STRAIN II, WATERBUCK. Date Experiment No. Animal I Percentage among short ______.._____ . ____Io ______,__ ~ stumpy forms _'_ 1912 September 7 1,220 Rat I 7 8 1,220 I 2 12 1,220 http://militaryhealth.bmj.com/ 16 1,220 !~ 17 1,220 I 39 18 1,220 I 45 19 1,220 I 21 20 1,220 50 23 1,220 36 24 1,220 47 " I Average ... I 30'7 on September 27, 2021 by guest. (3) MORPHOLOGY OF STRAIN HI, ORIBI. The following table gives the average length of this trypanosome as found in the rat, 500 trypanosomes in all, and also the length of the longest and shortest :- J R Army Med Corps: first published as 10.1136/jramc-22-02-03 on 1 February 1914. Downloaded from TABLE VII,-MEASUREMENTS OF THE LENGTH OF THE TRYPANOSOME OF STRAIN Ill, ORIB!, In microns Date Method of fixing Method of staining Average Maximum Minimum length I length I length 1912 Osmic acid Giemsa 21'6 33'0 16'0 TABLE VIII.-DISTRIEUTION IN RESPECT TO LENGTH OF 500 INDIVIDUALS m' THE TRYPANOSOME OF STRAIN Ill, ORIEL In microns 16 17 I 18 19 20 23 24 ------___ 1 __------_~J--=_ 19 Total", .. , .. , 1 10 I 22 77 109 90 57 28 Percentages .. , .. , 0'2 2'0 4'4 15'4 21'S 18'0 I 11'4 5'6 3'8 I In microns H I I 30 31 32 35 ------~ ~ ------~ ~ Total .. , .. , .. , 23 15 21 14 i 6 5 2 1 Protected by copyright. Percentages '.. , .. 4'6 3'0 4'2 I 2'8 I 1'2 1'0 0'4 0'2 CHART 3,-Curve representing the Distribution, by Percentages, in respect to Length, of 500 Individuals of the Trypanosome of Strain III, Oribi, taken on nine consecutive days from Rat 992, Microns L 13 14 /5 16 17 16 19 20 21 22 23 24 20 Z6 27 28 Z9 30 8' 112 33 34 35 3637 .38 23 1% 1\ 2' 20 I http://militaryhealth.bmj.com/ '9 .a \, ,17 '6 I \ ~/S .oq,4 nl .., /5 ~ '2 ;:11 ~ \ ClI '0 I 0.. 9 S on September 27, 2021 by guest. 7 6 1\ 5 1\ I~ J..I\ 4 ... .. J ~ j 2 1"- 1/ I I'b.. 11 r.... ~ J R Army Med Corps: first published as 10.1136/jramc-22-02-03 on 1 February 1914. Downloaded from D. Bl'uce, D. Hal'vey, A. E. Hamerton and Lady Bl'uce 157 TABLE- IX,-PERCENTAGES OF POSTERIOR-NUCLEAR FORMS FOUND AMONG THE SHORT AND STUMPY VARIETIES OF THE TRYPANOSOME OF STRAIN Ill, ORIBI, Percentage among short Date I No, Animal l~xperiment apd stumpy forms 1912 August 1 992 Rat 12 " 2! 992 14 992 " 3 10 5 992 34 6 992 15 7 992 42 9 992 " 29 " 10 992 52 12 992 42 " 13 992 53 Average 30'3 (4) MORPHOLOGY OF STRAIN IV, HARTEBEESTE. Protected by copyright. The following table gives t.he average length of this trypanosome as found in the rat, 500 trypanosomes in all, and also the length of the longest and shortest :- 'TABLE X,-MEASUREMENTS OF THE LENGTH OF THE TRYPANOSOME OF STRAIN IV, HARTEBEESTE, In microns Date Method of fixing Method of staining Average Ninimnnl length length 2i:l'5 1912 Osmic acid Giemsa 35'0 I 1S'O http://militaryhealth.bmj.com/ TABLE XL-DISTRIBUTION IN RESPECT TO LENGTH OF 500 INDIVIDUALS OF THE TRYPANOSOME OF STRAIN IV, HARTEBEESTE, In microns 18 19 20 21 22 23 24 25 26 ------Total .. , ... 1 12 53 SO 92 53 46 45 28 Percentages .. , ... 0'2 2'4 10'6 16'0 1S'4 10'6 9'2 9'0 5'6 on September 27, 2021 by guest. I In microns 27 28 29 30 31 32 33 34 35 ------Total ... .. - .. - 25 21 10 19 6 6 2 - 1 _ .. Percentages .. - 5-0 4-2 2-0 3'S 1-2 1-2 0-4 - 0'2 11 J R Army Med Corps: first published as 10.1136/jramc-22-02-03 on 1 February 1914. Downloaded from 158 Morphology of Va1"ivus Strains of the Trypanosome CHART 4.-Curve respecting' the Distribution, by Percentages, in respect to Le~gth, of 500 Individuals of the Trypanosome of Strain IV, Hartebeeste, taken on nine consecutive days from Rat 849. Microns D13 14 1,5 16 17 18 19 20 :11 2Z Z$ 2425 Z6 27 :18 29 30 51 32- 33 34 35 36 37 "8 ! 20 19 IS III 17 I 16 j 15 11 14 '" 13 QJ .oq12 1 ..,rdll I \ s:: 10 t '\ QJ 9 I\. ~8 \ I ClJ7 a.. Protected by copyright. 6 5 I' ... r-.., .3 J\ 2 J ~ I \. "'" IJ f'tI.. '- 1,.0 TABLE XII.-PERCENTAGES OF POSTERIOR-NUCLEAR FORMS FOUND AMONG THE SHORT AND STUMPY VARIETIES OF THE TRYPANOSOME OF STRAIN IV, HARTEBEESTE. Date lE'xpenmen t •N o. Animal Percentageand stumpy among forms short ------1------http://militaryhealth.bmj.com/ 1912 I July 19 ... ; 849 Rat 15 20 849 18 22 849 8 23 849 16 24 849 26 26 849 49 29 849 16 30. 849 38 " 31 849 52 August 1 .. , 849 45 Average 28'3 ... I on September 27, 2021 by guest. (5) MORPHOLOGY OF STRAIN V, HARTEBEESTE. The following table gives the average length of this trypanosome as found in the rat, 500 trypanosomes in all, and also the length of the longest and shortest :- J R Army Med Corps: first published as 10.1136/jramc-22-02-03 on 1 February 1914. Downloaded from D. Bruce, D.Harvey, A. E. Hamerton (J,nd Lady Bruce 159 TABLE XIII.--lY!EASUREMENTS OF THE LENGTH OF THE TRYPANOSOME OF STRAIN V, HARTEBEESTE. In microns Date Method of fixing Method of staining Average Maximum Minimum length I length I length 1912 Osmic acid Giemsa 22'6 I 34'0 15'0 TABLE XIV.-DISTRIBUTION IN RESPECT TO LENGTH OF 500 INDIVIDUALS OF THE TRYPANOSOME OF STRAIN V, HARTEBEESTE. In microns I 15 16 17 18 I 19 20 21 22 23 24 ------Total...... 1 1 11 -30-1-47- 79 51 51 44 37 Percentages ... 0'2 0'2 2'2 6'0 I 9'4 15'S 10'2 10'2 S'S 7'4 I Protected by copyright. In microns -- 25 26 27 28 29 30 31 32 33 34 ----_._------Total ...... 36 37 2S 24 11 3 S 1 - 2 Percentages ... 7'2 7'0 5'6 4'S 2'2 06 1'6 0'2 - 0'4 CHART 5.-Curve representing the Distribution, by Percentages, in respect to Length, of 500 Individuals of the Trypanosome of Strain V, Hartebeeste, takeu on nine consecutive days from Rat 1022. Microns 13 14 15 16 17 18 19 2021 2225 2425 26 Z7 28 29 .30~1 S:Z .53 .,4- 35 36 37 38 17 http://militaryhealth.bmj.com/ 16 15 1. 14 11' 13 0) 12 II _o~11'" 1 b!iI. ..,Id 10 Lb 1:9 I IJ .... ro- ~B , ~7 I\. 0...6 J on September 27, 2021 by guest. lL I, 5 , 4- -5 I 11 1\ 2. v I ~ I .. ~ I" ~ ~ J R Army Med Corps: first published as 10.1136/jramc-22-02-03 on 1 February 1914. Downloaded from 160 Morphology of Various 8tmins of the Trypanosome TABLE XV.-PERCENTAGES OF POSTERIOR-NUCLEAR FORMS FOUND AMONG THE SHORT AND STUMPY VARIETIES OF THE TRYPANOSOME OF STRAIN V, HARTEBEESTE. Percentage among short Date Experiment No. Animal and stumpy forms 1912 August 21 1,022 Rat 18 22 1,022 7 23 1;022 11 24 1,022 30 26 1,022 42 27 1,022 55 28 1,022 34 29 1,022 54 Sept~mber 2 1,022 50 Average ...... 1 33'4 I Protected by copyright. COMPARISON OF THE ,VILD GAME STRAINS WITH ONE ANO'l'HER. TABLE XVI.-MEASUREMENTS OF THE LENGTH OF THE TRYPANOSOME OF THE WILD GAME STRAINS. In microns Experi- Animal Number From what Date ment measured animal No_ AYerage Maximum Minimum length length length ------1912 783 I Reedbuck 500 Rat 21-7 34-0 16-0 1912 1,180 Waterbuck 500 23-5 33-0 16'0 1912 863 Oribi .. - 500 " 21-6 33-0 16-0 http://militaryhealth.bmj.com/ 1912 799 Hartebeeste 500 " 23'5 35'0 18'0 1912 957 500 I ;; 22-6 34'0 15-0 " ._------,,- --2~OO--\-Ave~;- 22-6 35'0 15'0 I COMPARISON OF THE CURVES OF 'l'HE WILD GAME STRAINS. Unlike the curves of the human strains, these are all remarkably alike, and there can be little doubt that the same sp'ecies of trypano on September 27, 2021 by guest. some is being dealt with in all five of the wild game strains. The wild game curves resemble strains H, IV, and V of the human strains, described in a former paper, and also those found by Kinghorn and Yorke in the Luangwa Valley. J R Army Med Corps: first published as 10.1136/jramc-22-02-03 on 1 February 1914. Downloaded from D. Bruce, D. Harvey, A. E. Hamerton and Lady Bruce 161 TABLE XVII.-DISTRIBUTION IN RESPECT TO LENGTH OF 2,500 INDIVIDUALS OF THE TRYPANOSOME OF THE FIVE WILD GAME STRAINS. In microns 15 ! 16 17 18 19 20 21 22 23 24 ------I ------Total...... 1 8 53 118 252 381 348 285 200 162 Percen tages ... -1-- 0'3 2'1 4'7 10'0 15'2 13'9 11'4 8'0 6'5 I In microns 25 26 27 28 29 30 31 32 33 34 3.'> ------I --- -7-1-3- Total '" ... 149 135 125 110 62 55 53 12 1 Percentages 6'0 5'4 5'0 4'4 2'5 2'2 1'5 0,5 0'3 0,1 - ... Protected by copyright. I CHART 6.-Composite Curve representing the Distribution, by Percentages, in respect to -Length, of 2,500 Individuals of the Trypanosome of the Wild Game Strains. Microns 13 14 15 16 '7 18 19 20 .21 22 23 2-4- ;zS' 26 27 28 29 3D 31 32 .33 .304- 35 36 37 38 17 http://militaryhealth.bmj.com/ 16 15 " 14 I J3 \ If) 12 Vii \ ·o~ , cd 10 1 .pg I c: I 1\ v8 "\ ~ 7 ~6 l~· 5 I t'o.. on September 27, 2021 by guest. 04- I i"\ 3 2 I i"'-~ If I "- .I I\>- f.o.. J R Army Med Corps: first published as 10.1136/jramc-22-02-03 on 1 February 1914. Downloaded from 162 Morphology of Various Strains of the Trypanosome This composite curve resembles the human Strain II, E--. TABLE XVIII.-COMPARISON OF THE PERCENTAGES OF POSTERIOR-NUCLEAR FORMS FOUND AMONG THE SHORT AND STUMPY VARIETIES OF THE TRYPANOSOME OF THE FIVE WILD GAME STRAINS_ Date Experiment Animal Percentage among short No. and stumpy forms ------I 1912 783 ! Reedbuck 8-4 1912 1180' I Waterbuck ::: 30'7 1912 863 i Oribi .. , ... 30'3 1912 779 ! Hartebeeste 28'3 1912 957 33'4 Average ···1 26'2 It is evident from these tables and charts that the vanous strains of this trypanosome, as they occur in wild game, are remarkably alike. This is what mi~ht be expected. Here the Protected by copyright. trypanosome is at home: it is leading a natural life. It may be supposed to be saved from variation by constantly passing and repassing between the antelope and the tsetse-fly. COMPARISON OF THE HUMAN STRAIN WITH THE WILD GAME STRAIN. TABLE XIX.-AvERAGE LENGTH OF THE TRYPANOSOME OF THE HUMAN AND WILD GAME STRAINS. In microns Number of Strain trypanosomes Animal http://militaryhealth.bmj.com/ measured Average Minimum length I Maximumlength I length Human 3600 Rat 24'2 38'0 15'0 Wild-game .. ·1, 2500 22'6 .35'0 15'0 1 1 The length of the trypanosomes of the human strain found Ill' white rats only is included in this table, in order to permit of comparIson with the wild game strain, which is also taken from rats. on September 27, 2021 by guest. The curves (Chart 7) differ from each other in such a marked manner as to be of no use in deciding as to the identity of the human and wild game strains. In spite of this, however, by a comparison of the two strains morphologically and by the susceptibility of the different experimental animals to their patho- J R Army Med Corps: first published as 10.1136/jramc-22-02-03 on 1 February 1914. Downloaded from D. Bruce, D. Harvey, A. E. HamertQn and Lady Bruce 163 genic action, the Commission are driven for the present to the decision. that the two strains belong to the same species of trypanosome. CHART 7.-0urves representing the Distribntion, by Percentages, in respect to Length, of 3,600 Individuals of tbeTrypanosome of the Human Strain, and 2,500 of the Wild Game Strain. -- Microns ~ 13 14 IS 16 17 16 19 ZO 21 22 Z324 25 2627 2829 30 31 .32 3334- 3536 37 .38 I 17 16 15 .Q. _ Wild GiJme Strain. t--t- I 14 !l ____ Human Strain. f-I- 13 ~ \ 12 ., 11 1 ~ Q) J \ s>- .00 10 , rd 9 L .., "-. I .10\ -G l= 8 .,.' Protected by copyright. , \ ~ 7 .,'- 6 / "[",- ~ "ill. CL 5 I r-a.. ''', ,0 4 I1 ~ Q. J ,/ J' Ib.. 'Q, - 2 """ ... 1 ri ~ 14' 1"0.. 1-0-.:,: ~ -0. TABLE XX.-PERCENTAGES OF POSTERIOR·NUCLEAR FORMS FOUND AMONG THE SHORT AND STUMPY VARIETIES OF THE TRYPANOilOME OF THE HUMAN AND WILD GAME STRAINS. http://militaryhealth.bmj.com/ Date Strain Average, Maximum, Minimum, percentage percentage percentage ------1912 .. . Human 52'0 1912 ...... Wild Game '" 33'4 CONCLUSIONS. (1) The five wild game strains resemble each other closely, and all belong to the same species of trypanosome. (2) The wild game strains and the human strains, although on September 27, 2021 by guest. they differ to some extent, also belong to the same species. (3) This species is T. rhodesiense (Stephens and Fantham). (4) There is some reason for the belief that T. rhodesiense and T. brllcei (Plimmer and Bradford) are one and the same species.