Molecular epidemiology of ticks and tick-borne disease, host resistance and development of novel pathogen vaccines

蜱和蜱传疾病的分子流行病学、宿主抵抗力和新型病原体疫苗的开发

• 批准号: BB/L004739/1
• 负责人: Brian Shiels
• 金额: $ 54.64万
• 依托单位: University of Glasgow
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2014
• 资助国家: 英国
• 起止时间: 2014 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FL004739%2F1
• 关键词: Molecular; epidemiology; ticks; tick; borne

Tick-borne diseases (TBD) affect 80% of the world's cattle population, and are a significant threat to global food security. Tropical theileriosis caused by Theileria annulata is an important tick borne disease of cattle and buffalo in India, with estimated losses of $499 million per annum). Cattle and buffalo are also infected with Babesia, and the rickettsia, Anaplasma and Erlichia. Control of TBD has been largely by using acaracides to kill ticks but resistance and environmental damage are reducing the use of these compounds. Drug treatment is available but the cost is prohibitive for many farmers and with recent reports of parasite drug resistance, is not a long-term option for control. Live vaccines have been developed but have problems in terms of production, delivery, the treat of disease and transmission of contaminating infections. Vaccinated animals are likely to become infected and generate a carrier state that, for theileriosis, caiusese considerable economic loss. Thus, new methods of control are needed for the future if livestock productivity and food security is to be increased.There is not a wealth of epidemiological data from India on TBD. Available studies primarily used classical parasitological methods and limited to small geographical areas and cross sectional sampling. Knowledge of the relative importance of the pathogens and tick species, and the role of cattle breeds and buffalo in transmission and clinical disease is sketchy. T. annulata, Babesia bigemina and Anaplasma marginale range in prevalence across different regions and the most common tick vectors are Hyalomma anatolicum anatolicum and Rhipicephalus microplus. In general it is known that, young calves suffer clinical disease and most adult animals carry the infection but disease is less common. Both buffalos and native cattle are more resistant to disease compared to highly productive European breeds, which are highly susceptible. However, there is a pay-off with breeds that are disease resistant, because production is reduced, and crossbred calves are still susceptible to disease. Moreover, it has been shown that animals carrying Theileria parasites suffer substantial economic loss. For full productivity a disease free state requires to be reached. To develop more effective control strategies it is necessary to understand in detail TBD epidemiology in India. Genetic traits that confer breed resistance also need to be identified so that resistant animals with higher productivity can be bred. Strategies that also operate to block pathogen transmission by ticks should also be studied, since the ideal scenario for full productivity is a disease free state. The proposed project will have three related aims/objectives: 1) undertake an extensive molecular epidemiological analysis of tick borne disease and develop models to predict the impact of different approaches of control; 2) investigate the nature of breed resistance with respect to infection with Theileria annulata and 3) develop novel vaccines against tropical theileriosis, with emphasis on blocking transmission of the pathogen by the tick vector. All three objectives are designed to provide greater knowledge of the status of TBD in India with emphasis on improvement of strategies to control disease and reduce economic loss. While infections transmitted by ticks are a greater priority for India, significant levels of disease in livestock in the UK are caused by tick borne pathogens: e.g. Anaplasma (Tick borne fever), staphlycoccal bacteria (Tick pyaemia), Babesia (Red water fever) and the louping ill virus. Developing tools and models for epidemiology of TBD and investigating the nature of breed resistance and transmission blocking strategies is, therefore, of relevance to both countries.

蜱传疾病（TBD）影响了世界上80%的牛群，是对全球粮食安全的重大威胁。由环形泰勒虫（Theileria annulata）引起的热带泰勒虫病是印度牛和布法罗的重要蜱传播疾病，估计每年损失4.99亿美元。牛和布法罗也感染了巴氏杆菌、立克次体、无形体和立克次体。TBD的控制主要是通过使用杀螨剂杀死蜱，但抗药性和环境破坏正在减少这些化合物的使用。药物治疗是可用的，但费用对许多农民来说是令人望而却步的，最近有报道说寄生虫抗药性，这不是一个长期的控制选择。已经开发了活疫苗，但是在生产、递送、疾病治疗和污染性感染的传播方面存在问题。接种疫苗的动物很可能被感染并产生带菌者状态，这对于泰勒虫病来说会造成相当大的经济损失。因此，如果要提高牲畜生产力和粮食安全，就需要新的控制方法。现有的研究主要使用传统的寄生虫学方法，仅限于小的地理区域和横断面抽样。病原体和蜱种类的相对重要性，以及牛品种和布法罗在传播和临床疾病中的作用的知识是粗略的。T.环状蜱、双芽巴贝虫和边缘无浆体在不同地区流行，最常见的蜱虫媒介是安纳托利璃眼蜱和微小扇头蜱。一般来说，已知幼仔患有临床疾病，大多数成年动物携带感染，但疾病不太常见。水牛和本地牛对疾病的抵抗力比高生产力的欧洲品种更强，而欧洲品种非常容易受到疾病的影响。然而，有一个回报与品种是抗病的，因为产量减少，杂交小牛仍然容易受到疾病。此外，已经表明携带泰勒虫寄生虫的动物遭受巨大的经济损失。为了充分生产力，需要达到无疾病状态。为了制定更有效的控制策略，有必要详细了解印度TBD的流行病学。赋予品种抗性的遗传性状也需要被鉴定，以便能够培育具有更高生产力的抗性动物。还应研究阻断蜱传播病原体的策略，因为实现完全生产力的理想方案是无病状态。拟议的项目将有三个相关的目的/目标：1）对蜱传疾病进行广泛的分子流行病学分析，并开发模型来预测不同控制方法的影响; 2）调查品种对环形泰勒虫感染的抗性性质; 3）开发针对热带泰勒虫病的新型疫苗，重点是阻断蜱媒传播病原体。所有这三个目标的目的是提供更多的知识，TBD在印度的地位，重点是改善战略，以控制疾病和减少经济损失。虽然蜱传播的感染在印度是一个更优先的问题，但英国牲畜中的重大疾病是由蜱传播的病原体引起的：例如无形体（蜱传播热），葡萄球菌细菌（蜱脓毒症），巴氏杆菌（红水热）和louping病病毒。因此，开发TBD流行病学的工具和模型，调查品种耐药性和传播阻断策略的性质，对这两个国家都具有重要意义。

项目成果

A parasite DNA binding protein with potential to influence disease susceptibility acts as an analogue of mammalian HMGA transcription factors.

• DOI: 10.1371/journal.pone.0286526
• 发表时间: 2023
• 期刊: PloS one
• 影响因子: 3.7

Additional file 6: of Identification of candidate transmission-blocking antigen genes in Theileria annulata and related vector-borne apicomplexan parasites

附加文件 6：环状泰勒虫和相关媒介传播的顶复门寄生虫中候选传播阻断抗原基因的鉴定

• DOI: 10.6084/m9.figshare.c.3795769_d6
• 发表时间: 2017
• 作者: Lempereur L

Additional file 5: of Identification of candidate transmission-blocking antigen genes in Theileria annulata and related vector-borne apicomplexan parasites

附加文件 5：环形泰勒虫和相关媒介传播的顶复门寄生虫中候选传播阻断抗原基因的鉴定

• DOI: 10.6084/m9.figshare.c.3795769_d5
• 发表时间: 2017
• 作者: Lempereur L

Additional file 1: of Identification of candidate transmission-blocking antigen genes in Theileria annulata and related vector-borne apicomplexan parasites

附加文件 1：环形泰勒虫和相关媒介传播的顶复门寄生虫中候选传播阻断抗原基因的鉴定

• DOI: 10.6084/m9.figshare.c.3795769_d1
• 发表时间: 2017
• 作者: Lempereur L

Prevalence of Tick-borne Pathogens in Co-grazed Dairy Bovines Differs by Region and Host-type in Tamil Nadu, India

• DOI: 10.4172/2329-888x.1000177
• 发表时间: 2017-05
• 期刊: Advances in Dairy Research
• 作者: G. Ponnudurai;S. Larcombe;R. Velusamy;N. Rani;S. Kolte;B. Rubinibala;A. Alagesan;B. Rekha;B. Shiels