Institute of Medical Microbiology and Hygiene, University of Freiburg, Hermann-Herder-Strasse 11, Freiburg D-79104, Germany.
BMC Vet Res. 2013 Nov 28;9:235. doi: 10.1186/1746-6148-9-235.
Anaplasma phagocytophilum is a Gram-negative bacterium that replicates obligate intracellularly in neutrophils. It is transmitted by Ixodes spp. ticks and causes acute febrile disease in humans, dogs, horses, cats, and livestock. Because A. phagocytophilum is not transmitted transovarially in Ixodes spp., it is thought to depend on reservoir hosts to complete its life cycle. In Europe, A. phagocytophilum was detected in roe deer, red deer, wild boars, and small mammals. In contrast to roe deer, red deer and wild boars have been considered as reservoir hosts for granulocytic anaplasmosis in humans, dogs, and horses according to groESL- and ankA-based genotyping. A. phagocytophilum variants infecting small mammals in Europe have not been characterized extensively to date.
We amplified the total ankA open reading frames of 27 strains from voles and shrews. The analysis revealed that they harboured A. phagocytophilum strains that belonged to a distinct newly described ankA gene cluster. Further, we provide evidence that the heterogeneity of ankA gene sequences might have arisen via recombination.
Based on ankA-based genotyping voles and shrews are unlikely reservoir hosts for granulocytic anaplasmosis in humans, dogs, horses, and livestock in Europe.
嗜吞噬细胞无形体是一种革兰氏阴性细菌，在中性粒细胞中严格进行细胞内复制。它通过硬蜱属的蜱传播，引起人类、狗、马、猫和家畜的急性发热性疾病。由于嗜吞噬细胞无形体在硬蜱属中不能经卵传递，因此被认为依赖储存宿主来完成其生命周期。在欧洲，已经在獐鹿、马鹿、野猪和小型哺乳动物中检测到了嗜吞噬细胞无形体。与獐鹿不同，根据 groESL 和 ankA 基因分型，马鹿和野猪被认为是人类、狗和马中粒细胞无形体病的储存宿主。迄今为止，尚未对欧洲小型哺乳动物中感染的无形体变体进行广泛的特征描述。
我们从田鼠和鼩鼱中扩增了 27 株的总 ankA 开放阅读框。分析表明，它们携带的嗜吞噬细胞无形体菌株属于一个新描述的 ankA 基因簇。此外，我们提供的证据表明 ankA 基因序列的异质性可能是通过重组产生的。
基于 ankA 基因分型，在欧洲，田鼠和鼩鼱不太可能是人类、狗、马和家畜中粒细胞无形体病的储存宿主。
