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The Crimean-Congo hemorrhagic fever virus (CCHFV), a member of the genus Orthonairovirus and family Nairoviridae, is transmitted by ticks and causes severe hemorrhagic disease in humans. To study the epidemiology of CCHFV in different ecosystems in Xinjiang, China, a total of 58,932 ticks were collected from Tarim Basin, Junggar Basin, Tianshan Mountain, and Altai Mountain from 2014 to 2017. Hyalomma asiaticum asiaticum was the dominant tick species in Tarim and Junggar basins, whereas Dermacentor nuttalli and Hyalomma detritum were found in Tianshan Mountain and Altai Mountain, respectively. Reverse transcription-polymerase chain reaction of the CCHFV small (S) genome segment was used for the molecular detection. The CCHFV-positive percentage was 5.26%, 6.85%, 1.94%, and 5.56% in Tarim Basin, Junggar Basin, Tianshan Mountain, and Altai Mountain, respectively. Sequences of the S segment were used for phylogenetic analysis and the results showed that the newly identified CCHFV strains belonged to two clades. Our study confirms that H. asiaticum asiaticum is the major vector of CCHFV in desert habitats which is consistent with previous studies, and also suggests that H. detritum and D. nuttalli are emerging vectors for CCHFV in Xinjiang. Moreover, this study reports the presence of CCHFV in the mountain habitat of Xinjiang for the first time, suggesting that future surveillance of CCHFV should also include mountainous areas. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12250-018-0016-3) contains supplementary material, which is available to authorized users.

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne zoonosis, caused by CCHF virus (CCHFV) and which there are no diagnostic or therapeutic strategies. The C-terminus of glycoprotein (Gc) encoded by the CCHFV M gene is responsible for CCHFV binding to cellular receptors and acts as a neutralizing-antibody target. In this study, a modified biosynthetic peptide technique (BSP) was used to identify fine epitopes of Gc from the CCHFV YL04057 strain using rabbit antiserum against CCHFV-Gc. Six B cell epitopes (BCEs) and one antigenic peptide (AP) were identified: E1 (88VEDASES94), E2 (117GDRQVEE123), E3 (241EIVTLH246), AP-4 (281DFQVYHVGNLLRGDKV296), E5a (370GDTP QLDL377), E5b (373PQLDLKAR380), and E6 (443HVRSSD448). Western blotting analysis showed that each epitope interacted with the positive serum of sheep that had been naturally infected with CCHFV, and the results were consistent with that of Dot-ELISA. The multiple sequence alignment (MSA) revealed high conservation of the identified epitopes among ten CCHFV strains from different areas, except for epitopes AP-4 and E6. Furthermore, three-dimensional structural modeling showed that all identified epitopes were located on the surface of the Gc "head" domain. These mapped epitopes of the CCHFV Gc would provide a basis for further increase our understanding CCHFV glycoprotein function and the development of a CCHFV epitope-based diagnostics vaccine and detection antigen.