Yurchenko Oksana O, Dubina Dmytro O, Vynograd Nataliya O, Gonzalez Jean-Paul
1 State Body "I.I. Mechnikov Ukranian Anti-Plague Research Institute of the Ministry of Health of Ukraine ," Odessa, Ukraine .
2 Danylo Halytsky Lviv National Medical University , Lviv, Ukraine .
Vector Borne Zoonotic Dis. 2017 Aug;17(8):550-557. doi: 10.1089/vbz.2016.2094. Epub 2017 Jun 27.
Tick-borne encephalitis (TBE) is the most common tick-borne viral infection in Eurasia; thousands of human cases are annually reported from several European countries. Several tick species are vectors of the tick-borne encephalitis virus (TBEV), while TBE appears to be spreading from the Eurasian continent westward to Europe. Fifteen study sites were chosen from five territories of southern Ukraine, including Odessa, Mykolaiv, Kherson Oblast, the Autonomous Republic of Crimea, and Sevastopol. Tick collection was performed in spring season of three consecutive years (1988-1990) using either flagging technique or direct collection of specimens feeding on cattle. A total of 15,243 tick imagoes and nymphs were collected from nine species, including Dermacentor marginatus, D. reticulatus, Haemaphysalis parva, H. punctata, Hyalomma marginatum, Ixodes ricinus, Rhipicephalus bursa, R. rossicus, and R. sanguineus, pooled in 282 monospecific samples. Supernatant of grinded pool was used for inoculation to suckling mice for virus isolation. Eight TBEV isolates were identified from ticks among six study sites. Ticks showed a minimum infection rate from 0.11% to 0.81%. Phylogenetic analysis of the envelope (E) protein gene of seven isolates, assigned all to the European subtype (TBEV-Eu) showing a maximum identity of 97.17% to the "Pan" TBEV-Eu reference strain. Compared to 104 TBEV-Eu isolates they clustered within the same clade as the Pan reference strain and distinguished from other TBEV-Eu isolates. Amino acid sequence analysis of the South Ukrainian TBEV-Eu isolates revealed the presence of four amino acid substitutions 67 (N), 266 (R), 306 (V), and 407 (R), in the ectodomains II and III and in the stem-anchor region of the E protein gene. This study confirmed TBEV-Eu subtype distribution in the southern region of Ukraine, which eventually overlaps with TBEV-FE (Far Eastern subtype) and TBEV-Sib (Siberian subtype) domains, showing the heterogeneity of TBEV circulating in Ukraine.
蜱传脑炎（TBE）是欧亚大陆最常见的蜱传病毒感染；几个欧洲国家每年报告数千例人类病例。几种蜱类是蜱传脑炎病毒（TBEV）的传播媒介，而TBE似乎正从欧亚大陆向西蔓延至欧洲。从乌克兰南部的五个地区选取了15个研究地点，包括敖德萨、尼古拉耶夫、赫尔松州、克里米亚自治共和国和塞瓦斯托波尔。在连续三年（1988 - 1990年）的春季，采用拖旗法或直接采集吸食牛血的标本进行蜱虫采集。共从包括边缘革蜱、网纹革蜱、微小牛蜱、刻点血蜱、边缘璃眼蜱、蓖麻硬蜱、柏氏扇头蜱、罗氏扇头蜱和血红扇头蜱在内的9个物种中采集了15243只蜱成虫和若虫，汇集为282个单物种样本。研磨后的样本上清液用于接种乳鼠以进行病毒分离。在6个研究地点的蜱虫中鉴定出8株TBEV分离株。蜱虫的最低感染率为0.11%至0.81%。对7株分离株的包膜（E）蛋白基因进行系统发育分析，所有分离株均属于欧洲亚型（TBEV-Eu），与“泛”TBEV-Eu参考株的最大同一性为97.17%。与104株TBEV-Eu分离株相比，它们与泛参考株聚集在同一进化枝内，并与其他TBEV-Eu分离株区分开来。对乌克兰南部TBEV-Eu分离株的氨基酸序列分析显示，在E蛋白基因的胞外结构域II和III以及茎锚区域存在4个氨基酸替换，分别为67位（N）、266位（R）、306位（V）和407位（R）。本研究证实了TBEV-Eu亚型在乌克兰南部地区的分布，该地区最终与TBEV-FE（远东亚型）和TBEV-Sib（西伯利亚亚型）区域重叠，显示出在乌克兰传播的TBEV的异质性。
