Laboratoire de Parasitologie, Institution de la Recherche et de l'Enseignement Supérieur Agricoles and Univ. Manouba, École Nationale de Médecine Vétérinaire de Sidi Thabet, Sidi Thabet, Tunisia.
Department of Animal Medicine (Infectious Diseases), Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt.
Transbound Emerg Dis. 2020 Mar;67 Suppl 1:8-25. doi: 10.1111/tbed.13312.
Tropical theileriosis caused by the apicomplexan hemoparasite Theileria annulata is a tick-borne disease that constraints livestock production in parts of Europe, Asia and Africa. Four Hyalomma tick species transmit T. annulata in at least eight Africa countries (Mauritania, Morocco, Algeria, Tunisia, Egypt, Sudan, South Sudan and Ethiopia). The two dominant T. annulata vector ticks present in Africa, H. scupense and H. anatolicum, underlie two different patterns of transmission, which in turn greatly influence the epidemiology of tropical theileriosis. H. dromedarii and H. lusitanicum are also capable of transmitting T. annulata in North Africa, but their roles are associated with specific production systems and agro-ecological contexts. The emergence of resistance to the most widely used theilericidal compound, buparvaquone, continues to limit the effectiveness of chemotherapy. In addition, acaricide use is increasingly becoming unsustainable. Deployable T. annulata attenuated live vaccines established from local strains in Tunisia, Sudan and Egypt are available, and recent work has indicated that these vaccines can be protective under conditions of natural transmission. However, vaccination programmes may vary over space and time due to differences in the prevalence of disease amongst cattle populations, as well seasonal variation in vector activity. We review recent descriptive and analytical surveys on the epidemiology of T. annulata infection with reference to (a) demographic aspects such as breeds and ages of cattle herds previously exposed to distinct T. annulata infection pressures and (b) seasonal dynamics of tick activity and disease transmission. We then discuss how the wider endemic patterns that we delineate can underpin the development and execution of future vaccination programmes. We also outline options for integrated control measures targeting tick vectors and husbandry practices.
由顶复门的血液寄生虫泰勒虫引起的热带泰勒虫病是一种蜱传疾病，它限制了欧洲、亚洲和非洲部分地区的牲畜生产。四种钝缘蜱属的蜱在至少 8 个非洲国家（毛里塔尼亚、摩洛哥、阿尔及利亚、突尼斯、埃及、苏丹、南苏丹和埃塞俄比亚）传播泰勒虫。在非洲，两种主要的泰勒虫传播蜱，即 H. scupense 和 H. anatolicum，存在两种不同的传播模式，这反过来又极大地影响了热带泰勒虫病的流行病学。H. dromedarii 和 H. lusitanicum 也能够在北非传播泰勒虫，但它们的作用与特定的生产系统和农业生态环境有关。对最广泛使用的杀泰勒虫化合物，双羟萘酸噻嘧啶的耐药性不断出现，继续限制了化疗的效果。此外，杀蜱剂的使用正变得越来越不可持续。已经有来自突尼斯、苏丹和埃及的当地菌株建立的可部署的热带泰勒虫弱毒活疫苗，最近的研究表明，在自然传播的条件下，这些疫苗可以起到保护作用。然而，由于牛群中疾病的流行率以及媒介活动的季节性变化，疫苗接种计划可能会因空间和时间的不同而有所不同。我们回顾了最近关于泰勒虫感染的描述性和分析性调查，参考了（a）以前暴露于不同泰勒虫感染压力的牛群的种群特征，如品种和年龄，以及（b）蜱活动和疾病传播的季节性动态。然后，我们讨论了我们所描绘的更广泛的地方性模式如何为未来疫苗接种计划的制定和执行提供支持。我们还概述了针对蜱媒介和畜牧业实践的综合控制措施的选择。
