Infectious Diseases Branch, Division of Communicable Disease Control, California Department of Public Health, Sacramento, California, USA.
Vector Borne Zoonotic Dis. 2013 Jun;13(6):376-81. doi: 10.1089/vbz.2012.1137. Epub 2013 Mar 14.
Tick-borne relapsing fever (TBRF) is endemic in mountainous regions of the western United States. In California, the principal agent is the spirochete Borrelia hermsii, which is transmitted by the argasid tick Ornithodoros hermsi. Humans are at risk of TBRF when infected ticks leave an abandoned rodent nest in quest of a blood meal. Rodents are the primary vertebrate hosts for B. hermsii. Sciurid rodents were collected from 23 sites in California between August, 2006, and September, 2008, and tested for serum antibodies to B. hermsii by immunoblot using a whole-cell sonicate and a specific antigen, glycerophosphodiester phosphodiesterase (GlpQ). Antibodies were detected in 20% of rodents; seroprevalence was highest (36%) in chipmunks (Tamias spp). Seroprevalence in chipmunks was highest in the Sierra Nevada (41%) and Mono (43%) ecoregions and between 1900 and 2300 meters elevation (43%). The serological studies described here are effective in implicating the primary vertebrate hosts involved in the maintenance of the ticks and spirochetes in regions endemic for TBRF.
蜱传回归热（TBRF）在美国西部多山地区流行。在加利福尼亚州，主要病原体是螺旋体 Borrelia hermsii，由革螨 Ornithodoros hermsi 传播。当感染的蜱虫离开废弃的啮齿动物巢穴寻找血食时，人类有感染 TBRF 的风险。啮齿动物是 B. hermsii 的主要脊椎动物宿主。2006 年 8 月至 2008 年 9 月，从加利福尼亚州的 23 个地点采集了松鼠科啮齿动物，并通过使用全细胞超声提取物和特定抗原甘油磷酸二酯磷酸二酯酶（GlpQ）的免疫印迹法检测血清中针对 B. hermsii 的抗体。在 20%的啮齿动物中检测到了抗体；在花栗鼠（Tamias spp）中血清阳性率最高（36%）。在内华达山脉（41%）和莫诺（43%）生态区以及海拔 1900 至 2300 米处，花栗鼠的血清阳性率最高（43%）。此处描述的血清学研究有效地表明，在 TBRF 流行地区，维持蜱虫和螺旋体的主要脊椎动物宿主参与其中。
