Silveira F T, Lainson R, Shaw J J, Póvoa M M
Trans R Soc Trop Med Hyg. 1982;76(6):830-2. doi: 10.1016/0035-9203(82)90119-5.
Major endemic areas of visceral leishmaniasis in Brazil are located in the drier, poorly forested regions, principally in the northeastern States such as Ceará and Bahia. Cases of the human disease in the Amazon Region are rare, very sporadic, and seldom present opportunities for epidemiological study. Following the report of a fatal case near Salvaterra, the Island of Marajó, Pará State, a preliminary investigation has resulted in the isolation of a parasite regarded as Leishmania donovani chagasi from the viscera and skin of an apparently healthy fox, Cerdocyon thous, captured in the same locality. This represents the third recorded isolation of the parasite from this species of fox in the Amazon Region. The inapparent nature of the infections supports the suggestion that this canid may represent the primitive natural host of L. d. chagasi. C. thous is commonly associated with forested or wooded areas, and enzymic profiles for the enzymes ASAT, ALAT, PGM, GPI, MDH, MPI, G6PD, PEP and ACP failed to distinguish an isolate of L. d. chagasi from this animal in Pará from others obtained from cases of human visceral leishmaniasis in the neighbouring States of Maranhão, Ceará and Bahia. This suggests that the major, present-day endemics may have originated from a primary silvatic enzootic.
巴西内脏利什曼病的主要流行地区位于较为干燥、森林覆盖率低的区域，主要在东北部的塞阿拉州和巴伊亚州等州。亚马逊地区的人类病例罕见，非常零散，很少有进行流行病学研究的机会。在帕拉州马拉若岛萨尔瓦特拉附近报告了一例致命病例后，初步调查从在同一地点捕获的一只看似健康的食蟹狐（Cerdocyon thous）的内脏和皮肤中分离出一种被认为是杜氏利什曼原虫恰加斯亚种（Leishmania donovani chagasi）的寄生虫。这是该寄生虫在亚马逊地区从这种狐狸身上的第三次记录分离。感染的隐性性质支持了这种犬科动物可能是杜氏利什曼原虫恰加斯亚种原始自然宿主的观点。食蟹狐通常与森林或树木繁茂的地区有关，对天冬氨酸转氨酶（ASAT）、丙氨酸转氨酶（ALAT）、磷酸葡萄糖变位酶（PGM）、葡萄糖磷酸异构酶（GPI）、苹果酸脱氢酶（MDH）、磷酸甘露糖异构酶（MPI）、葡萄糖-6-磷酸脱氢酶（G6PD）、磷酸烯醇丙酮酸羧激酶（PEP）和酸性磷酸酶（ACP）等酶的酶谱分析未能将从帕拉州这种动物身上分离出的杜氏利什曼原虫恰加斯亚种与从邻近的马拉尼昂州、塞阿拉州和巴伊亚州人类内脏利什曼病病例中获得的其他分离株区分开来。这表明当今的主要地方病可能起源于原发性森林动物病。
