Jia Yuqing, Zhang Yu, Wu Xuanchen, Dong Zhihui, Xie Songsong, Li Wei, Liu Quan, Lu Xiaobo, Wang Yuanzhi
The People's Hospital of Xixian, Xinyang, China.
Department of Basic Medicine, School of Medicine, Shihezi University, Shihezi, China.
PLoS Negl Trop Dis. 2024 Jun 13;18(6):e0012168. doi: 10.1371/journal.pntd.0012168. eCollection 2024 Jun.
Tacheng tick virus 2 (TcTV-2) is an emerging tick-borne virus belonging to the genus Uukuvirus in the family Phenuiviridae. Initially isolated in 2019 from a patient in Xinjiang Uygur Autonomous Region (XUAR), northwestern China, who developed fever and headache after a tick bite, TcTV-2 was concurrently molecularly detected in hard ticks across various countries, including China, Kazakhstan, Romania, and Turkey. This study conducted a retrospective epidemiological investigation of TcTV-2 infection.
In this retrospective cohort study, we collected samples from 47 tick-bitten patients, 984 herdsmen, 7 Asian badgers, 13 red foxes, and 168 Hyalomma asiaticum tick egg batches. Patients' samples were primarily analyzed by using high-throughput sequencing, targeting the V3-V4 region of the bacterial 16S rRNA gene and viral cDNA libraries. Typical tick-borne pathogens were further confirmed using RT-PCR and detected in Asian badgers, red foxes and Hy. asiaticum tick egg batches. We also conducted enzyme-linked immunosorbent assay (ELISA) to detected specific IgM and IgG antibodies against TcTV-2 in herdsmen. Phylogenetic analysis was performed to genetically characterize TcTV-2 detected in this study.
TcTV-2 was detected in various samples, including blood, urine, and throat swabs from 12.77% (6/47) tick-bitten patients. It was found in blood samples of 14.29% (1/7) of wild badgers, 7.69% (1/13) of red foxes, and 13.69% (23/168) of Hy. asiaticum egg batches. Furthermore, ELISA results revealed that 9.55% (94/984) of the serum samples (34 from males and 60 from females) were tested positive for TcTV-2-specific IgG, while 2.95% (29/984, 7 males and 22 females) showed positivity for TcTV-2-specific IgM. Additionally, 1.02% (10/984, 4 males and 6 females) of the sera tested positive for both TcTV-2-specific IgM and IgG. Phylogenetic analysis indicated that the TcTV-2 strains detected in this study were genetically similar, regardless of their origin and host species.
Clinical symptoms of TcTV-2 infection in patients are nonspecific, with common symptoms including headache, fever, asthenia, vomiting, myalgia, rash, and meningitis-like signs. TcTV-2 can be detected in blood, urine, and throat swab samples of infected patients. Among local herdsmen, 9.55% tested positive for TcTV-2-specific IgG and 2.95% for TcTV-2-specific IgM. Importantly, TcTV-2 can be transovarially transmitted in Hy. asiaticum ticks, and the Asian badgers and red foxes are potential reservoirs of TcTV-2.
塔城蜱传病毒2（TcTV-2）是一种新出现的蜱传病毒，属于白蛉病毒科乌库病毒属。2019年首次从中国西北部新疆维吾尔自治区（XUAR）一名患者身上分离出来，该患者被蜱叮咬后出现发热和头痛症状，同时在中国、哈萨克斯坦、罗马尼亚和土耳其等多个国家的硬蜱中也检测到了TcTV-2的分子存在。本研究对TcTV-2感染进行了回顾性流行病学调查。
在这项回顾性队列研究中，我们收集了47名被蜱叮咬患者、984名牧民、7只亚洲獾、13只赤狐和168批亚洲璃眼蜱卵的样本。患者样本主要通过高通量测序进行分析，靶向细菌16S rRNA基因的V3-V4区域和病毒cDNA文库。使用逆转录聚合酶链反应（RT-PCR）进一步确认典型的蜱传病原体，并在亚洲獾、赤狐和亚洲璃眼蜱卵批次中进行检测。我们还进行了酶联免疫吸附试验（ELISA），以检测牧民中针对TcTV-2的特异性IgM和IgG抗体。进行系统发育分析以对本研究中检测到的TcTV-2进行基因特征描述。
在各种样本中检测到了TcTV-2，包括12.77%（6/47）被蜱叮咬患者的血液、尿液和咽拭子。在14.29%（1/7）的野生獾血液样本、7.69%（1/13）的赤狐血液样本和13.69%（23/168）的亚洲璃眼蜱卵批次中发现了该病毒。此外，ELISA结果显示，9.55%（94/984）的血清样本（34份来自男性，60份来自女性）检测出TcTV-2特异性IgG呈阳性，而2.95%（29/984，7名男性和22名女性）的血清样本检测出TcTV-2特异性IgM呈阳性。此外，1.02%（10/984，4名男性和6名女性）的血清样本中TcTV-2特异性IgM和IgG均呈阳性。系统发育分析表明，本研究中检测到的TcTV-2毒株在基因上相似，无论其来源和宿主物种如何。
患者感染TcTV-2的临床症状无特异性，常见症状包括头痛、发热、乏力、呕吐、肌痛、皮疹和脑膜炎样体征。在感染患者的血液、尿液和咽拭子样本中可检测到TcTV-2。在当地牧民中，9.55%检测出TcTV-2特异性IgG呈阳性，2.95%检测出TcTV-2特异性IgM呈阳性。重要的是，TcTV-2可在亚洲璃眼蜱中经卵传播，亚洲獾和赤狐是TcTV-2的潜在宿主。
