背景:中东和北非(MENA)为蜱的繁殖和传播提供了最佳的气候条件。该地区对蜱传病原体的研究很少。尽管最近在埃及影响动物的各种蜱传疾病的表征和分类学解释方面取得了进展,尚未对TBP(蜱传病原体)状态进行全面检查.因此,本研究旨在检测埃及壁虱携带的病原体的患病率。
结果:进行了一项为期四年的基于PCR的研究,以检测埃及三种经济上重要的壁虱物种所携带的广泛的壁虱传播病原体(TBP)。约有86.7%(902/1,040)的调查骆驼的风力机蜱被发现为无羊毛虫阳性(18.8%),反刍动物埃里希菌(16.5%),非洲立克次体(12.6%),环化泰利氏菌(11.9%),精氨酸支原体(9.9%),伯氏疏螺旋体(7.7%),类螺旋体内共生体(4.0%),肝虫犬(2.4%),伯氏柯西氏菌(1.6%)和婴儿利什曼原虫(1.3%)。在3.0%(27/902)的Hy中记录到双重共感染。单发滴答声,在9.6%(87/902)的Hy中发现了三重共感染(三种病原体同时感染tick)。单发滴答声,而多重共感染(蜱被≥4种病原体同时感染)占12%(108/902)。在从狗和绵羊收集的1,435个调查的Rhipicephalusrutilus蜱中,816只(56.9%)蜱虫窝藏犬巴贝斯(17.1%),立克次体(16.2%),犬埃里希氏菌(15.4%),H.犬(13.6%),博。伯格多费里(9.7%),L.婴儿(8.4%),犬中的C.burnetii(7.3%)和伊凡氏锥虫(6.6%),和242个(16.9%)蜱有西里氏菌(21.6%),卵裂虫(20.0%)和Eh。绵羊的反刍动物(0.3%)。双倍,三重,多重合并感染占11%(90/816),7.6%(62/816),和10.3%(84/816),分别在Rh。来自狗的rutilus,而双重和三重合并感染占30.2%(73/242)和2.1%(5/242),分别在Rh。来自绵羊的rutilus。牛的约92.5%(1,355/1,465)的Rhipicephalusrhalusticks携带了边缘无性体的负担(21.3%),babesiabigemina(18.2%),Babesiabovis(14.0%),疏螺旋体(12.8%),非洲R.(12.4%),Th.环状物(8.7%),博。伯格多费里(2.7%),和Eh。反刍动物(2.5%)。双倍,三重,多重合并感染占1.8%(25/1,355),11.5%(156/1,355),和12.9%(175/1,355),分别。检测到的病原体序列与现有数据库具有98.76-100%的相似性,与来自其他非洲的最接近序列的遗传差异在0.0001至0.0009%之间,亚洲人,和欧洲国家。系统发育分析显示,检测到的病原体与其他主要来自非洲和亚洲国家的分离株之间存在密切的相似性。
结论:连续PCR检测由蜱传播的病原体对于克服这些感染对宿主的影响是必要的。埃及当局应对动物进口实施更多限制,以限制该国蜱传病原体的出现和重新出现。这是埃及首次对TBP进行深入调查。
BACKGROUND: The Middle East and North Africa (MENA) offer optimal climatic conditions for tick reproduction and dispersal. Research on tick-borne pathogens in this region is scarce. Despite recent advances in the characterization and taxonomic explanation of various tick-borne illnesses affecting animals in Egypt, no comprehensive examination of TBP (tick-borne pathogen) statuses has been performed. Therefore, the present study aims to detect the prevalence of pathogens harbored by ticks in Egypt.
RESULTS: A four-year PCR-based study was conducted to detect a wide range of tick-borne pathogens (TBPs) harbored by three economically important tick species in Egypt. Approximately 86.7% (902/1,040) of the investigated Hyalomma dromedarii ticks from camels were found positive with Candidatus Anaplasma camelii (18.8%), Ehrlichia ruminantium (16.5%), Rickettsia africae (12.6%), Theileria annulata (11.9%), Mycoplasma arginini (9.9%), Borrelia burgdorferi (7.7%), Spiroplasma-like endosymbiont (4.0%), Hepatozoon canis (2.4%), Coxiella burnetii (1.6%) and Leishmania infantum (1.3%). Double co-infections were recorded in 3.0% (27/902) of Hy. dromedarii ticks, triple co-infections (simultaneous infection of the tick by three pathogen species) were found in 9.6% (87/902) of Hy. dromedarii ticks, whereas multiple co-infections (simultaneous infection of the tick by ≥ four pathogen species) comprised 12% (108/902). Out of 1,435 investigated Rhipicephalus rutilus ticks collected from dogs and sheep, 816 (56.9%) ticks harbored Babesia canis vogeli (17.1%), Rickettsia conorii (16.2%), Ehrlichia canis (15.4%), H. canis (13.6%), Bo. burgdorferi (9.7%), L. infantum (8.4%), C. burnetii (7.3%) and Trypanosoma evansi (6.6%) in dogs, and 242 (16.9%) ticks harbored Theileria lestoquardi (21.6%), Theileria ovis (20.0%) and Eh. ruminantium (0.3%) in sheep. Double, triple, and multiple co-infections represented 11% (90/816), 7.6% (62/816), and 10.3% (84/816), respectively in Rh. rutilus from dogs, whereas double and triple co-infections represented 30.2% (73/242) and 2.1% (5/242), respectively in Rh. rutilus from sheep. Approximately 92.5% (1,355/1,465) of Rhipicephalus annulatus ticks of cattle carried a burden of Anaplasma marginale (21.3%), Babesia bigemina (18.2%), Babesia bovis (14.0%), Borrelia theleri (12.8%), R. africae (12.4%), Th. annulata (8.7%), Bo. burgdorferi (2.7%), and Eh. ruminantium (2.5%). Double, triple, and multiple co-infections represented 1.8% (25/1,355), 11.5% (156/1,355), and 12.9% (175/1,355), respectively. The detected pathogens\' sequences had 98.76-100% similarity to the available database with genetic divergence ranged between 0.0001 to 0.0009% to closest sequences from other African, Asian, and European countries. Phylogenetic analysis revealed close similarities between the detected pathogens and other isolates mostly from African and Asian countries.
CONCLUSIONS: Continuous PCR-detection of pathogens transmitted by ticks is necessary to overcome the consequences of these infection to the hosts. More restrictions should be applied from the Egyptian authorities on animal importations to limit the emergence and re-emergence of tick-borne pathogens in the country. This is the first in-depth investigation of TBPs in Egypt.