Assessing the stability of parasite communities through perturbation experiments

通过扰动实验评估寄生虫群落的稳定性

• 批准号: NE/G006830/1
• 负责人: Andy Fenton
• 金额: $ 33.09万
• 依托单位: University of Liverpool
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2009
• 资助国家: 英国
• 起止时间: 2009 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FG006830%2F1
• 关键词: Assessing; stability; parasite; communities; through

In the past twenty years, there has been a surge of interest in the role of disease on individual health and its effects on host populations. These studies and, indeed, the majority of disease control programmes of humans and domestic animals tend to consider individual infections in isolation. However, hosts are typically infected by many parasite species at any one time. For example, humans, particularly in the developing world, can be simultaneously co-infected with a variety of parasites: around 40.3 million people are currently infected with HIV/AIDS, over one third of the population worldwide has TB, and over one fourth has soil transmitted helminths. Importantly, these co-infecting parasites are unlikely to occur in isolation within each host, indeed there may be a vast network of interactions between them. These interactions may arise through direct competition between parasites within each host. However, they may also be indirect, possibly through competition for shared resources (bottom-up interactions) or via the host's immune system (top-down interactions). In this case, immune responses raised against one parasite may also affect other co-infecting parasite species. Alternatively, if the host is combating one parasite type it may not be able to mount an effective response against another. Therefore there may be a complex network of subtle, and difficult to detect interactions between parasite species that result in a diverse, interactive community within each individual host. Clearly, understanding how these communities are shaped is vital for the design of truly effective and sustainable disease control programs. If control approaches only consider one parasite species there may be unpredictable consequences for disease caused by other, co-infecting parasites. However, current approaches to measure parasite interactions are purely observational and, so far, have produced unclear information about their strength or existence. We propose to adopt a new, direct way of measuring interactions using classical community ecology perturbation experiments, by removing certain parasites from wild wood mice and measuring what happens to the remaining parasite species - if they increase after the target parasites have been removed then this suggests that the target species was previously suppressing their abundance. By repeating this process for all main parasite groups in the wood mice, we can build a more complete picture of how these parasite communities are shaped by the interactions between species. Putting all these interactions into a mathematical model will allow us to predict how such parasite communities will respond to more complex treatments, such as the removal of two species at the same time. If our model predictions prove accurate for more complex co-treatment strategies, then these within host network approaches may provide a vital tool for developing long-term disease control strategies in other host species, such as humans, domestic animals or wildlife threatened to extinction by infectious diseases. It is gradually being realised that parasite co-infections play an important role in the occurrence and management of many diseases of human concern. Given the increasing concerns about emerging infectious diseases around the globe, it has never been more pressing to develop a genuine understanding of the factors affecting parasite invasion, transmission, persistence, and control. This project will be a major step in that direction.

在过去的二十年中，人们对疾病对个人健康的作用及其对宿主人群的影响引起了人们的兴趣。这些研究，实际上，大多数人类和家畜的疾病控制计划倾向于孤立地考虑个人感染。但是，宿主通常一次被许多寄生虫物种感染。例如，人类，尤其是在发展中国家的人类，可以同时与各种寄生虫共同感染：目前，大约有4030万人感染了艾滋病毒/艾滋病，全球超过三分之一的人口中有三分​​之一的人患有结核病，超过四分之一以上的人是土壤传播的。重要的是，这些共同感染的寄生虫不太可能在每个宿主中孤立地发生，实际上，它们之间可能存在大量的相互作用网络。这些相互作用可能是通过每个宿主内的寄生虫之间的直接竞争而产生的。但是，它们也可能是间接的，可能是通过竞争共享资源（自下而上的交互）或通过主机的免疫系统（自上而下的交互）的竞争。在这种情况下，针对一种寄生虫产生的免疫反应也可能影响其他共同感染的寄生虫物种。另外，如果主机正在对抗一种寄生虫类型，则可能无法对另一种寄生虫进行有效响应。因此，可能存在一个复杂的微妙网络，并且很难检测到寄生虫物种之间的相互作用，从而导致每个宿主内部都有多样化的互动社区。显然，了解这些社区的塑造方式对于设计真正有效和可持续的疾病控制计划的设计至关重要。如果控制方法仅考虑一种寄生虫物种，则可能会对其他共同感染寄生虫引起的疾病产生不可预测的后果。但是，当前测量寄生虫相互作用的方法纯粹是观察性的，到目前为止，已经产生了有关其强度或存在的不清楚的信息。我们建议通过去除野生木鼠的某些寄生虫并测量其余寄生虫物种发生的事情，以使用经典群落生态扰动实验来测量相互作用的新型方法 - 如果将目标寄生虫在去除靶寄生虫后增加，那么这表明目标物种先前抑制了它们的丰富性。通过为木鼠中所有主要寄生虫组重复此过程，我们可以更完整地了解这些寄生虫群落如何由物种之间的相互作用塑造。将所有这些相互作用纳入数学模型将使我们能够预测这种寄生虫社区将如何应对更复杂的治疗方法，例如同时去除两个物种。如果我们的模型预测对更复杂的共同处理策略证明是准确的，那么宿主网络方法中的这些方法可能会为在其他宿主物种（例如人类，家畜或野生动物）中发展长期疾病控制策略提供至关重要的工具，威胁到传染病灭绝。逐渐意识到，寄生虫共感染在许多人类关注的疾病的发生和管理中起着重要作用。鉴于对全球新兴传染病的越来越担心，对影响寄生虫入侵，传播，持久性和控制的因素的真正理解从未如此紧迫。该项目将是朝这个方向迈出的重要一步。

项目成果

Translational Rodent Models for Research on Parasitic Protozoa-A Review of Confounders and Possibilities.

• DOI: 10.3389/fcimb.2017.00238
• 发表时间: 2017
• 期刊: Frontiers in cellular and infection microbiology
• 影响因子: 5.7
• 作者: Ehret T;Torelli F;Klotz C;Pedersen AB;Seeber F
• 通讯作者: Seeber F

The predicted impact of resource provisioning on the epidemiological responses of different parasites.

• DOI: 10.1111/1365-2656.13751
• 发表时间: 2022-08
• 期刊: JOURNAL OF ANIMAL ECOLOGY
• 影响因子: 4.8
• 作者: Erazo, Diana;Pedersen, Amy B.;Fenton, Andy
• 通讯作者: Fenton, Andy

Dances with worms: the ecological and evolutionary impacts of deworming on coinfecting pathogens.

• DOI: 10.1017/s0031182013000590
• 发表时间: 2013-08
• 期刊: Parasitology
• 影响因子: 2.4
• 作者: Fenton A

The reliability of observational approaches for detecting interspecific parasite interactions: comparison with experimental results

检测种间寄生虫相互作用的观察方法的可靠性：与实验结果的比较

• DOI: 10.5167/uzh-97442
• 发表时间: 2014
• 作者: Fenton, Andy

Analysis of a summary network of co-infection in humans reveals that parasites interact most via shared resources.

• DOI: 10.1098/rspb.2013.2286
• 发表时间: 2014-05-07
• 期刊: Proceedings. Biological sciences
• 作者: Griffiths EC;Pedersen AB;Fenton A;Petchey OL
• 通讯作者: Petchey OL