Tularemia is a zoonotic disease that transmitted to humans and domestic animals by wildlife, especially rodents and hares, to humans and domestic animals. There are some evidences of the circulation of F. tularensis in rodents, livestock, human populations, and surface waters in western parts of Iran. In this study, we investigated the exposure of livestock and ranchers to F. tularensis in the endemic regions of western Iran. Blood samples were collected from 289 sheep, 103 cattle, and 51 ranchers in 2018. Animal sera were tested by standard tube agglutination method. The specific IgGs against F. tularensis were evaluated by ELISA in human sera. Moreover, the extracted DNAs from 50 sheep spleen samples were evaluated using TaqMan real-time PCR for the presence of ISFtu2 and FopA genes. All animal sera and spleen samples were negative for tularemia. Of the 51 human samples, two samples were seropositive and one sample showed a borderline status for tularemia. Serologic evidence of F. tularensis in the ranchers but negative results in the livestock indicates different transmission routes in human populations and animals in western Iran. Therefore, drinking contaminated water, contact to wildlife or rodents and arthropod bite should be considered as probable routes in the suspicious areas.

Tularemia是一种人畜共患病，它通过野生生物传播给人类和家畜，尤其是啮齿动物和野兔，传播给人类和家畜。有一些证据表明，伊朗西部地区的啮齿类动物，牲畜，人口和地表水中存在土拉氏梭菌的循环。在这项研究中，我们调查了伊朗西部流行地区的牲畜和牧场主暴露于图拉菌。2018年从289只绵羊，103头牛和51位牧场主中采集了血样。通过标准管凝集法检测动物血清。抗图拉菌的特异性IgG通过ELISA在人血清中评估。此外，使用TaqMan实时PCR对从50只绵羊脾脏样品中提取的DNA进行了ISFtu2和FopA基因的评估。所有动物血清和脾脏样本均未检出妥拉血。在51份人类样本中，有2份呈血清反应阳性，有1份显示Tularemia处于临界状态。牧场主中存在土拉弗朗西斯菌的血清学证据，但牲畜的阴性结果表明伊朗西部人口和动物的传播途径不同。因此，在可疑地区，应考虑饮用受污染的水，接触野生动植物或啮齿动物以及节肢动物叮咬。