Anhui Province in China bears the highest burden of Severe Fever with Thrombocytopenia Syndrome (SFTS) nationwide; however, comprehensive surveys of tick vectors remain limited. We aimed to characterize tick species composition and to evaluate spatial patterns of vector distribution across SFTS-endemic areas in the province. In this study, a combined morphological and molecular approach was utilized for tick identification. Ticks were initially identified based on their morphological characteristics. Subsequently, gene fragments of the large subunit ribosomal RNA (16 S rRNA) and the cytochrome c oxidase subunit I (COI) were amplified to confirm species identification. A total of 3504 ticks were collected, including 2021 larvae (57.68%), 662 nymphs (18.89%), 677 females (19.04%), and 144 males (4.11%). A total of 1483 tick specimens (including nymphs and adults) were identified: Haemaphysalis longicornis was the most prevalent species (account for 71.07%), followed by Rhipicephalus sanguineus and Haemaphysalis flava. In total, 13 tick species from five genera were identified, seven of which—Haemaphysalis campanulata, Rhipicephalus turanicus, Haemaphysalis doenitzi, Haemaphysalis formosensis, Haemaphysalis yeni, Dermacentor steini, and Amblyomma testudinarium—represented new records for Anhui. The relative abundance of H. longicornis exhibited significant spatial heterogeneity (χ²=483.332, P < 0.001). Notably, in areas with high incidence of SFTS, the prevalence of H. longicornis was marked higher (88.39%, 95% CI: 86.41%-90.36%) compared with regions with low SFTS incidence (28.12%, 95% CI: 23.11%-33.12%) and non-case regions (44.16%, 95% CI: 36.22%-52.09%). In the areas with high incidence of SFTS, the infection rate and tick density of the external environment and animals were higher than those in the areas with low incidence and no cases. Phylogenetic analysis based on 16 S rRNA gene showed that the tested samples clustered within their respective GenBank species. Within the genus Haemaphysalis, H. longicornis exhibited closer relationships with H. hystricis and H. doenitzi. In the genus Rhipicephalus, R. turanicus was closely related to R. sanguineus. COI analysis indicated geographical differentiation in H. longicornis populations from Jinzhai and Qimen.This study characterizes the ixodid tick fauna in Anhui Province and reports several newly documented species. These findings highlight the need for enhanced surveillance of tick vectors and pathogen monitoring to support effective SFTS prevention and control.

Survey of hard ticks in high-incidence area of Severe Fever with Thrombocytopenia Syndrome in China

期刊论文
发表日期：

2025年12月22日

查看全文

Min Wang,
Lei Gong,
Yujie Wang,
Lesheng Zhang,
Fengfeng Wang,
Qi Wang,
Qingyue Li,
Xiaohe Ma,
Zhiguo Cao,
Jiabing Wu

摘要

Anhui Province in China bears the highest burden of Severe Fever with Thrombocytopenia Syndrome (SFTS) nationwide; however, comprehensive surveys of tick vectors remain limited. We aimed to characterize tick species composition and to evaluate spatial patterns of vector distribution across SFTS-endemic areas in the province. In this study, a combined morphological and molecular approach was utilized for tick identification. Ticks were initially identified based on their morphological characteristics. Subsequently, gene fragments of the large subunit ribosomal RNA (16 S rRNA) and the cytochrome c oxidase subunit I (COI) were amplified to confirm species identification. A total of 3504 ticks were collected, including 2021 larvae (57.68%), 662 nymphs (18.89%), 677 females (19.04%), and 144 males (4.11%). A total of 1483 tick specimens (including nymphs and adults) were identified: Haemaphysalis longicornis was the most prevalent species (account for 71.07%), followed by Rhipicephalus sanguineus and Haemaphysalis flava. In total, 13 tick species from five genera were identified, seven of which—Haemaphysalis campanulata, Rhipicephalus turanicus, Haemaphysalis doenitzi, Haemaphysalis formosensis, Haemaphysalis yeni, Dermacentor steini, and Amblyomma testudinarium—represented new records for Anhui. The relative abundance of H. longicornis exhibited significant spatial heterogeneity (χ²=483.332, P < 0.001). Notably, in areas with high incidence of SFTS, the prevalence of H. longicornis was marked higher (88.39%, 95% CI: 86.41%-90.36%) compared with regions with low SFTS incidence (28.12%, 95% CI: 23.11%-33.12%) and non-case regions (44.16%, 95% CI: 36.22%-52.09%). In the areas with high incidence of SFTS, the infection rate and tick density of the external environment and animals were higher than those in the areas with low incidence and no cases. Phylogenetic analysis based on 16 S rRNA gene showed that the tested samples clustered within their respective GenBank species. Within the genus Haemaphysalis, H. longicornis exhibited closer relationships with H. hystricis and H. doenitzi. In the genus Rhipicephalus, R. turanicus was closely related to R. sanguineus. COI analysis indicated geographical differentiation in H. longicornis populations from Jinzhai and Qimen.This study characterizes the ixodid tick fauna in Anhui Province and reports several newly documented species. These findings highlight the need for enhanced surveillance of tick vectors and pathogen monitoring to support effective SFTS prevention and control.