Host-seeking ticks collected in Shimonoseki, Yamaguchi Prefecture.

<p>Host-seeking ticks collected in Shimonoseki, Yamaguchi Prefecture.</p

Prevalence of <i>Borrelia</i> sp. in wild boars collected from Shimonoseki, Yamaguchi Prefecture.

<p>Prevalence of <i>Borrelia</i> sp. in wild boars collected from Shimonoseki, Yamaguchi Prefecture.</p

Epidemiological study of relapsing fever borreliae detected in <i>Haemaphysalis</i> ticks and wild animals in the western part of Japan

<div><p>The genus <i>Borrelia</i> comprises arthropod-borne bacteria, which are infectious agents in vertebrates. They are mainly transmitted by ixodid or argasid ticks. In Hokkaido, Japan, <i>Borrelia</i> spp. were found in deer and <i>Haemaphysalis</i> ticks between 2011 and 2013; however, the study was limited to a particular area. Therefore, in the present study, we conducted large-scale surveillance of ticks and wild animals in the western part of the main island of Japan. We collected 6,407 host-seeking ticks from two regions and 1,598 larvae obtained from 32 engorged female ticks and examined them to elucidate transovarial transmission. In addition, we examined whole blood samples from 190 wild boars and 276 sika deer, as well as sera from 120 wild raccoons. We detected <i>Borrelia</i> spp. in <i>Haemaphysalis flava</i>, <i>Haemaphysalis megaspinosa</i>, <i>Haemaphysalis kitaokai</i>, <i>Haemaphysalis longicornis</i>, and <i>Haemaphysalis formosensis</i>. In addition, we isolated a strain from <i>H</i>. <i>megaspinosa</i> using Barbour-Stoenner-Kelly medium. The minimum infection rate of ticks was less than 5%. Transovarial transmission was observed in <i>H</i>. <i>kitaokai</i>. Phylogenetic analysis of the isolated strain and DNA fragments amplified from ticks identified at least four bacterial genotypes, which corresponded to the tick species detected. Bacteria were detected in 8.4%, 15%, and 0.8% of wild boars, sika deer, and raccoons, respectively. In this study, we found seasonal differences in the prevalence of bacterial genotypes in sika deer during the winter and summer. The tick activity season corresponds to the season with a high prevalence of animals. The present study suggests that a particular bacterial genotype detected in this study are defined by a particular tick species in which they are present.</p></div

Phylogenetic analysis of <i>glpQ</i> in <i>Borrelia</i> spp.

<p>The tree was constructed using the neighbor-joining method based on the Kimura two-parameter model. The phylogenetic branches were supported by >70% according to the bootstrap analysis. The bar indicates the percentage of sequence divergence. <i>Borrelia</i> sp. BF-16 (accession no. AB529436), <i>Borrelia</i> sp. Tick98M (AB529432), <i>Borrelia</i> sp. TA2 (AB529434), and <i>Borrelia</i> sp. Tortoise14H1 (AB529431) were used as outgroups (data not indicated). Pointing arrows and bold type indicate the results obtained in the present study. Numbers in parentheses represent GenBank accession numbers.</p

Collection sites.

<p>The gray and black shading in the lower right large-scale map indicates Minabe town and Tanabe City in Wakayama Prefecture, respectively. The black shading in the upper left large-scale map indicates Shimonoseki City in Yamaguchi Prefecture. The geographic locations of the tick sampling site are designated by black or white dots. Reprinted from (<a href="http://www.freemap.jp/item/japan/japan1.html" target="_blank">http://www.freemap.jp/item/japan/japan1.html</a>) under a CC BY license, with permission from Keisuke Inoue, original copyright 2016.</p

Host-seeking ticks collected in Shimonoseki, Yamaguchi Prefecture.

<p>Host-seeking ticks collected in Shimonoseki, Yamaguchi Prefecture.</p

Larval ticks prepared from engorged females collected from wild boar or sika deer in Shimonoseki, Yamaguchi Prefecture.

<p>Larval ticks prepared from engorged females collected from wild boar or sika deer in Shimonoseki, Yamaguchi Prefecture.</p

Phylogenetic analysis of <i>flaB</i> in <i>Borrelia</i> spp.

<p>The tree was constructed using the neighbor-joining method based on the Kimura two-parameter model. The phylogenetic branches were supported by >70% according to the bootstrap analysis. The bar indicates the percentage of sequence divergence. <i>B</i>. <i>afzelii</i> VS461 (accession no. D63365), <i>B</i>. <i>burgdorferi</i> B31 (AB035617), and <i>B</i>. <i>garinii</i> 20047 (AB035602) were used as outgroups (data not indicated). Pointing arrows and bold type indicate the results obtained in the present study. TNB1904 is the raccoon sample from Wakayama Prefecture. Underlined samples were derived from ticks. Numbers in parentheses represent GenBank accession numbers.</p

Host-seeking ticks collected in Wakayama Prefecture.

<p>Host-seeking ticks collected in Wakayama Prefecture.</p