Department of Animal Medicine (Infectious Diseases), Faculty of Veterinary Medicine, Assiut University, 71526, Egypt; Institute of Infectology, Friedrich-Loeffler-Institut, Suedufer 10, 17493, Greifswald-Insel Riems, Germany.
Institute of Infectology, Friedrich-Loeffler-Institut, Suedufer 10, 17493, Greifswald-Insel Riems, Germany.
Ticks Tick Borne Dis. 2021 May;12(3):101676. doi: 10.1016/j.ttbdis.2021.101676. Epub 2021 Jan 26.
To address the lack of information on ticks infesting cattle in Egypt and the pathogens that they transmit, the current study aimed to (i) provide insight into tick species found on cattle in Egypt, (ii) identify the pathogens in ticks and their cattle hosts and (iii) detect pathogen associations in ticks and cattle. Tick samples and blood from their bovine hosts were collected from three different areas in Egypt (EL-Faiyum Oasis, Assiut Governorate and EL-Kharga Oasis). Tick species were identified by morphology and by sequence analysis of the cytochrome C oxidase subunit 1 (cox1) gene. Tick pools and blood samples from cattle were screened by the Reverse Line Blot hybridization (RLB) assay for the simultaneous detection of tick-borne pathogens, including Babesia, Theileria, Anaplasma, Ehrlichia, and Rickettsia spp., as well as the tick endosymbiont Midichloria mitochondrii. The RLB results were confirmed with specific conventional and semi-nested PCRs followed by sequencing. In total, 570 ticks (males, females and nymphs) were collected from 41 heads of cattle. Altogether 398 ticks belonged to the genus Hyalomma (397 Hyalomma excavatum and one Hyalomma scupense) while 172 ticks were identified as Rhipicephalus annulatus. Pooled H. excavatum ticks tested positive for several protozoa and bacteria with different minimum infection rates (MIRs): Theileria annulata (18.1 %), Babesia occultans (1.8 %), Anaplasma marginale (28.5 %), Anaplasma platys (0.25 %), Midichloria mitochondrii (11.6 %), Ehrlichia chaffeensis-like (1.8 %) and Ehrlichia minasensis (1 %). In R. annulatus, several agents were identified at different MIRs: T. annulata (2.3 %), B. bovis (0.6 %), A. marginale (18.0 %), A. platys (1.2 %), M. mitochondrii (2.9 %), E. minasensis (0.6 %). Pathogens co-detection in tick pools revealed A. marginale and T. annulata in 13.3 % samples followed by the co-detection of A. marginale and M. mitochondrii (8.4 %). In addition, triple co-detection with A. marginale, T. annulata and M. mitochondrii were found in 5.3 % of the tick pools. In cattle, the most common coinfection was with A. marginale and T. annulata (82.9 %) followed by the coinfection between A. marginale, T. annulata and B. bovis (4.9 %), A. marginale and B. bigemina (2.4 %) and finally the coinfection between T. annulata and B. occultans (2.4 %). Anaplasma platys, Babesia occultans, and E. minasensis were detected for the first time in Egypt in both cattle and ticks. These findings should be taken in consideration regarding human and animal wellbeing by the public health and veterinary authorities in Egypt.
为了解决埃及牛蜱感染和传播病原体方面信息不足的问题，本研究旨在：（i）了解埃及牛蜱的物种分布；（ii）鉴定蜱和牛宿主中的病原体；（iii）检测蜱和牛中的病原体关联。从埃及三个不同地区（法尤姆绿洲、阿西尤特省和盖尔加绿洲）采集了蜱和牛血样。通过形态学和细胞色素 C 氧化酶亚基 1（cox1）基因序列分析鉴定蜱的种类。采用反向线杂交（RLB）检测试剂盒对蜱类和牛血样进行检测，以同时检测包括巴贝虫、泰勒虫、无形体、埃立克体和立克次体属以及蜱共生体中微生物的感染情况。用特定的常规和半巢式 PCR 进行验证，随后进行测序。共从 41 头牛身上采集到 570 只蜱（雄性、雌性和若虫）。其中 398 只为伊氏锥虫属（397 只为 H. excavatum，1 只为 H. scupense），172 只为璃眼蜱属（Rhipicephalus annulatus）。H. excavatum 混合样本检测出多种原虫和细菌，其最小感染率（MIR）各不相同：环形泰勒虫（18.1%）、无浆体（1.8%）、边缘无形体（28.5%）、边缘无形体（0.25%）、中微生物（11.6%）、查菲埃立克体样菌（1.8%）和米纳斯无形体（1%）。在 R. annulatus 中，不同样本的检测出多种病原体，其最小感染率各不相同：环形泰勒虫（2.3%）、牛巴贝斯虫（0.6%）、边缘无形体（18.0%）、无形体（1.2%）、中微生物（2.9%）、米纳斯无形体（0.6%）。蜱混合样本的共检测结果显示，13.3%的样本中存在边缘无形体和环形泰勒虫，其次是边缘无形体和中微生物的共检测（8.4%）。此外，在 5.3%的蜱混合样本中还发现了三重共检测结果，包括边缘无形体、环形泰勒虫和中微生物。在牛中，最常见的混合感染是边缘无形体和环形泰勒虫（82.9%），其次是边缘无形体、环形泰勒虫和牛巴贝斯虫（4.9%）、边缘无形体、环形泰勒虫和双芽巴贝斯虫（2.4%）以及环形泰勒虫和无浆体（2.4%）。在埃及的牛和蜱中首次检测到边缘无形体、无浆体和米纳斯无形体。埃及公共卫生和兽医部门应考虑这些发现，以维护人类和动物的健康。
