Park Chun-Ho, Nakanishi Ataru, Hatai Hitoshi, Kojima Daisuke, Oyamada Toshifumi, Sato Hisaaki, Kudo Noboru, Shindo Junji, Fujita Osamu, Hotta Akitoyo, Inoue Satoshi, Tanabayashi Kiyoshi
Department of Veterinary Pathology, School of Veterinary Medicine, Kitasato University, Towada, Aomori 034-8628, Japan.
J Vet Med Sci. 2009 Dec;71(12):1629-35. doi: 10.1292/jvms.001629.
An adult male hare (Lepus brachyurus angustidens) was discovered in a moribund condition in the bush in the mountains of Aomori prefecture in Japan. Upon gross inspection, many ticks were found on the neck and the external ear regions, and more than half the ticks contained blood in the intestine. The skin around the tick bite wounds was alopecic and mildly thickened. At necropsy, enlargement of the cervical lymph nodes and spleen were observed. Histologically, acute necrotizing splenitis, lymphadenitis, hepatitis, pneumonia, myelitis, adrenalitis, and encephalitis with bacterial organisms were observed. The cutaneous lesions were chronic and cysts had formed in the areas marked by tick bites. Immunohistochemically, the organisms in the skin, liver, spleen, lymph nodes, lungs, adrenal glands, brain, bone marrow, and ticks were positive for F. tularensis antigen. Microbiological and polymerase chain reaction results were consistent with F. tularensis subsp. holarctica. Because the cutaneous lesions were more chronic than those in the visceral organs and F. tularensis was detected in the ticks, we inferred that F. tularensis was transmitted to the hare via tick bites.
在日本青森县山区的灌木丛中发现一只成年雄性野兔（Lepus brachyurus angustidens），处于濒死状态。大体检查时，在颈部和外耳道区域发现许多蜱虫，超过半数的蜱虫肠道内含有血液。蜱虫叮咬伤口周围的皮肤脱毛且轻度增厚。尸检时，观察到颈部淋巴结和脾脏肿大。组织学检查发现，存在急性坏死性脾炎、淋巴结炎、肝炎、肺炎、脊髓炎、肾上腺炎以及伴有细菌的脑炎。皮肤病变为慢性，蜱虫叮咬部位形成了囊肿。免疫组织化学检测显示，皮肤、肝脏、脾脏、淋巴结、肺、肾上腺、脑、骨髓和蜱虫中的病原体对土拉弗朗西斯菌抗原呈阳性反应。微生物学和聚合酶链反应结果与全北区土拉弗朗西斯菌亚种相符。由于皮肤病变比内脏器官的病变更具慢性，且在蜱虫中检测到土拉弗朗西斯菌，我们推断土拉弗朗西斯菌是通过蜱虫叮咬传播给野兔的。
