Visceral leishmaniasis (VL) is the fatal form of leishmaniasis. A newly emerging focus of zoonotic VL (ZVL) including 13 villages has been reported from Maraveh Tappeh County, Golestan province, north-eastern Iran. We investigated the effect of climatic and environmental factors on the occurrence of disease in this focus by geographical information systems (GIS) approaches and logistic regression models. The incidence rate of ZVL in human and dog population was estimated 1.2% and 27.3%, respectively, in the studied areas. Rock soil type (OR = 11.7), rainfall (OR = 1.04) and elevation (OR = 0.99) were found as determinants of ZVL. Also, almost all infected villages were in close proximity of rivers. Cavities of rock soil around rivers are assumed as suitable areas for sandfly resting and growth by providing shadow and moisture. Rainfall also provides appropriate moisture in semi-arid regions for survival of sandflies. The negative effect of higher altitude can be explained by some sandfly life-limiting conditions like freezing weather. Accordingly, regions with lower altitude and higher rainfall, covered by rock and in close proximity of rivers, are the hazard zones for ZVL in the Maraveh Tappeh. Air humidity, temperature, land cover type and slope were not predictors of disease in the current study. Further investigations on human population movement, probable reservoirs and vectors of disease can provide valuable data for modelling the future distribution of ZVL in the Iranian province.

中文翻译：

---

伊朗东北部农村地区人畜共患的内脏利什曼病新近出现的地缘气候因素。

内脏利什曼病（VL）是利什曼病的致命形式。伊朗东北部Golestan省的Maraveh Tappeh县已经报道了包括13个村庄在内的人畜共患病VL（ZVL）的新近出现。我们通过地理信息系统（GIS）方法和逻辑回归模型，研究了气候和环境因素对疾病发生的影响。在研究区域中，人和狗群中ZVL的发生率分别估计为1.2％和27.3％。发现岩石土壤类型（OR = 11.7），降雨（OR = 1.04）和高程（OR = 0.99）是ZVL的决定因素。另外，几乎所有受感染的村庄都在河流附近。通过提供阴影和水分，假定河流周围的岩土空洞是沙sand栖息和生长的合适区域。降雨还为半干旱地区的沙蝇提供了适当的水分。海拔较高的负面影响可以用某些限制沙蝇寿命的条件（例如冰冻天气）来解释。因此，海拔较低，降雨量较高，被岩石覆盖且紧邻河流的地区是Maraveh Tappeh中ZVL的危险地带。在当前研究中，空气湿度，温度，土地覆盖类型和坡度不是疾病的预测指标。对人口流动，可能的病原体和疾病传播媒介的进一步研究可以为模拟ZVL在伊朗省的未来分布提供有价值的数据。海拔较高的负面影响可以用某些限制沙蝇寿命的条件（例如冰冻天气）来解释。因此，海拔较低，降雨量较高，被岩石覆盖且紧邻河流的地区，是马拉维·塔佩（Maraveh Tappeh）ZVL的危险地带。在当前研究中，空气湿度，温度，土地覆盖类型和坡度不是疾病的预测指标。对人口流动，可能的病原体和疾病传播媒介的进一步研究可以为模拟ZVL在伊朗省的未来分布提供有价值的数据。海拔较高的负面影响可以用某些限制沙蝇寿命的条件（例如冰冻天气）来解释。因此，海拔较低，降雨量较高，被岩石覆盖且紧邻河流的地区，是马拉维·塔佩（Maraveh Tappeh）ZVL的危险地带。在当前研究中，空气湿度，温度，土地覆盖类型和坡度不是疾病的预测指标。对人口流动，可能的病原体和疾病传播媒介的进一步研究可以为模拟ZVL在伊朗省的未来分布提供有价值的数据。