Tacheng tick virus 1 (TcTV-1) was firstly found in a tick bitten patient in Qinghe County (border county of China-Mongolia), Xinjiang Uygur Autonomous Region (XUAR), and further detected in pastured cattle and sheep. Songling virus (SGLV) was isolated in tick-borne patients in Heilongjiang Province (border region of China-Russia) and Inner Mongolia Autonomous Region (border region of China-Mongolia). The aim of this study was to detect TcTV-1, SGLV and Tamdy virus (TAMV, first found in a tick bitten patient from Kyrgyzstan) in great gerbil. A total of 276 great gerbils were collected in Manas County (common county) and Altaw City (border city of China-Kazakhstan), XUAR, northwestern China. The total RNA of individual spleen tissue was extracted, and the viral L segments of TcTV-1, SGLV and TMAV were detected by transcriptase-polymerase chain reaction. The amplification products were cloned and sequenced, and phylogenetic analyses were conducted by MEGA7.0. The results indicated that 2.9% (8/276) and 2.2% (6/276) of spleens were respectively tested positive to the viral L segments for TcTV-1 and SGLV, and TAMV was not detected in these samples. SGLV in great gerbil shared 93.7% (236/252 nt) and 94.0% (78/83 aa) identities to that of SGLV (MT328776) detected in patients in northeastern China. TcTV-1 in great gerbil was the closest to that of TcTV-1 from a patient in China (MK554672) with 98.5% (797/809 nt) and 98.9% (265/268 aa) identities. This is the first molecular evidence for the presence of TcTV-1 and SGLV in great gerbil. SGLV presented highly genetic diversity correlated with their geographical location. Tamdy orthonairovirus surveillance in multiple border regions of China, Kazakhstan, Kyrgyzstan, Russia and Mongolia in more wild animals is necessary.

Tacheng tick virus 1 (TcTV-1), emerging tick-borne orthonairoviruses, was firstly isolated from a tick bite patient in northwestern China. However, TcTV-1 in livestock, wildlife, and potential vectors was still unknown. From 2017 to 2021, 1495 samples included 180 engorged adult female ticks, 180 egg batches, 84 larvae, 896 adult ticks, 148 livestock blood samples, and 7 spleens from red foxes were collected from 14 counties or cities of southern and eastern Kazakhstan, and northwestern China. The samples were tested for the presence of TcTV-1 using the viral L segments by reverse transcriptase–polymerase chain reaction (RT-PCR). The infection rates of TcTV-1 were 7.78% (14/180), 3.89% (7/180), and 2.47% (2/84) in engorged adult female Hyalomma asiaticum ticks and their offsprings (eggs and larvae), respectively. 6.45% (9/148) blood samples of livestock and 14.29% (1/7) spleen samples of red foxes tested positive to TcTV-1. TcTV-1 was detected in 13.08% (34/260) adult hard ticks from Kazakhstan and 5.35% (34/636) ticks from China. This findings suggests that i) the pastured cattle, sheep, camel and wild red fox act as natural reservoirs for TcTV-1; ii) TcTV-1 is detected in genera of Hyalomma, Dermacentor, Rhipicephalus and Ixodes both originated from northwestern China and southeastern Kazakhstan; and iii) Hy. asiaticum is a potential vector of TcTV-1 due to its transovarial transmission.