Health > Quarterly bulletin of the Health Organisation > Volume 3

204
THE NATURAL TRANSMISSION
2. The geographical distribution of Oriental sore does not
everywhere coincide with that of the visceral leishmaniases. Though
there are countries (Greece, Southern Italy, Spain, the Algerian
littoral) in which all three infections are met with, there are other
regions in which—up to the present at any rate—only one form has
been encountered ; for instance, the visceral leishmaniases have
never been observed in the Algerian Sahara,1 nor at Baghdad or
Aleppo,2 which are notoriously Oriental sore areas.
3. There is no cross-immunity between the Oriental sore and
the various visceral leishmaniases : Oriental sore immunises against
Oriental sore, but not against the other leishmania infections.
Visceral leishmaniases sometimes immunise against Oriental sore—
their virus behaving in this case towards L. tropica as a strong
towards a weak virus,3 but sometimes they do not immunise at all
or do so only incompletely.4 L. tropica, when injected intra-
dermally into monkeys and dogs, reproduces Oriental sore with
all its characteristics of an ulcerating lesion ; when, however,
viruses of visceral leishmaniases are injected intradermally into
the same animals, they cause the formation, in situ, of a hard,
fibrous and non-ulcerating nodule.5
C.—The discovery of canine visceral leishmaniasis6 raised at the
outset the problem of its specific identification : Was it or was it
not due to the same parasite as visceral leishmaniasis in man ?
Most of the writers who have set out to solve this problem have,
Donatien and Lestoquard, Algdrie medicals, loc. cit.). Similarly, the
cutaneous ulcerations observed in canine visceral leishmaniasis have nothing
in common with Oriental sore ; they are not primitive and circumscribed
lesions, but a sort of secondary and metastatic lesion which is the final phase of
a diffuse parasitical infiltration of the tegument (Adler and Theodor, Proc.
Roy. Soc., R, 110, 1932, pages 402-412) and which never constitutes the
whole of the disease, as does Oriental sore.
1 L. Parrot, A. Donatien and F. Lestoquard, Algirie mddicale, loc. cit.
2 S. Adler and O. Theodor, Ann. Trap. Med. and Parasit., XXIII, 1929,
pages 269-303.
3 Gh. Nicolle and Manceaux, Arch. Inst. Pasteur, Tunis, VII, 1912, pages
219-224.
4 A. Laveran, Leishmaniases, Masson, Pub. Paris, 1917, page 423 ; L. Parrot,
A. Donatien and F. Lestoquard, Arch. Inst. Pasteur d’Algerie, V, 1927,
pages 120-130.
« R. Row, Journ. Trap. Med. Hyg., XV, 1912, pages 327-328, and XVI, 1913,
pages 1-2 ; A. Laveran, loc. cit., page 421 ; L. Parrot, A. Donatien and
F. Lestoquard, loc. cit.,
8 Ch. Nicolle and Ch. Comte, C. R. Acad. Sc., April 6th, 1908.