Fallatah S A, Ghallab E H, Khater E I
Biology Department, College of Science, Imam Abdulrahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia.
Department of Entomology, Faculty of Science, Ain Shams University, Cairo, Egypt.
Trop Biomed. 2019 Jun 1;36(2):390-401.
Hard ticks are causative agents of physical illness and vectors of important diseases of human and livestock. The hard tick Hyalomma dromedarii Koch, 1844 is a major ectoparasite of livestock in the Kingdom of Saudi Arabia (KSA), of which, the onehumped dromedaries Camelus dromedarius is the most economically and culturally important and a potential reservoir of Middle East respiratory syndrome coronavirus (MERSCoV) disease. Here we report on the molecular phylogenetic diversity of H. dromedarii collected from camels in the Eastern Province of KSA based on the mitochondrial cytochrome oxidase I (COI) gene. Maximum likelihood (ML) phylogenetic analysis of COI sequences of the studied ticks identified 11 haplotypes. All H. dromedarii ticks from KSA belonged to eight haplotypes diverged into two distinguished genetic clades (A-B). These results indicate that H. dromedarii ticks from KSA are monophyletic species with two distinguished lineages with low intra-specific genetic divergence and sharply structured isolated populations with high level of genetic differentiation. This is a first report of DNA barcode of H. dromedarii ticks from KSA and the Arabian Peninsula, which is an important step towards broader phylogenetic studies on larger tick samples from the region. The studies are important for better understanding its interactions with camels and other hosts and role in zoonotic disease transmission (e.g. MERS-CoV or Alkhurma virus) to pinpoint effective control strategies.
硬蜱是身体疾病的病原体以及人类和牲畜重要疾病的传播媒介。1844年命名的单峰驼璃眼蜱（Hyalomma dromedarii Koch）是沙特阿拉伯王国牲畜的主要体外寄生虫，其中单峰骆驼（Camelus dromedarius）在经济和文化方面最为重要，并且是中东呼吸综合征冠状病毒（MERS-CoV）疾病的潜在宿主。在此，我们基于线粒体细胞色素氧化酶I（COI）基因，报告了从沙特阿拉伯东部省份骆驼身上采集的单峰驼璃眼蜱的分子系统发育多样性。对所研究蜱的COI序列进行的最大似然（ML）系统发育分析确定了11个单倍型。来自沙特阿拉伯的所有单峰驼璃眼蜱均属于8个单倍型，分为两个不同的遗传分支（A - B）。这些结果表明，来自沙特阿拉伯的单峰驼璃眼蜱是单系物种，有两个不同的谱系，种内遗传差异低，且隔离种群结构分明，遗传分化程度高。这是关于来自沙特阿拉伯和阿拉伯半岛的单峰驼璃眼蜱DNA条形码的首次报告，这是朝着对该地区更大规模蜱样本进行更广泛系统发育研究迈出的重要一步。这些研究对于更好地理解其与骆驼及其他宿主的相互作用以及在人畜共患病传播（如MERS-CoV或阿尔胡尔马病毒）中的作用以确定有效的控制策略具有重要意义。
