Workshop - Predicting Zoonotic Outbreaks: Building on the Plague Threshold Model

寄主-病原体动力学的真实世界研究往往跟不上理论概念的发展。这种不足特别令人遗憾的一个领域是这些概念在医学和兽医科学中的应用。一个具体的例子是建立疾病从野生动物宿主传播到人类(或家畜)种群/所谓的人畜共患疾病的高风险时间和/或地点的预测模型。这将是这次研讨会的主题。一个罕见的预测人畜共患病暴发的模型使用了哈萨克斯坦的淋巴腺鼠疫的长期数据。在那里，以及整个中亚大部分地区，鼠疫仍然是一个相当大的公共卫生问题，那里的主要宿主是大沙鼠沙鼠。这项研究证明了沙鼠体内存在“临界丰度阈值”，必须超过这个阈值，鼠疫才能在其宿主中形成(并构成威胁)，此外，由于它是基于过去沙鼠的丰度，该模型不仅具有描述性，而且还可以用于预测未来的暴发，即一个早期预警系统。随后，该模型的输出被用于开发一种预测性“专家系统”，哈萨克斯坦的公共卫生工作者正在试行该系统。拟议的研讨会的目的是以鼠疫模型为跳板，询问(I)利用临界丰度阈值和其他关键概念为威胁公共健康的野生动物中的其他疾病系统开发早期预警模型的前景是什么，以及需要哪些数据？事实上，简单的“门槛”模型可能会有多广泛的适用性？在什么情况下需要不同的(类型)模型？(2)如何最好地将这些模式转变为对公共卫生从业者有用的工具？公共卫生工作者想要/需要什么？这在发达国家和发展中国家之间有区别吗？如果是的话，又是如何区别的？(3)如何才能最好地将这样的预测纳入更大的风险分析和/或成本效益分析？“生态”模型/充其量/产生一种概率(带有置信度)，即疾病将在特定时间在特定地点出现。但是，如果疾病出现而没有采取行动，那么将无所作为的代价纳入其中的最佳方式是什么？同样，事实证明不必要的行动成本也是如此？为了考虑“社会”因素(例如，在未经治疗的暴发后失去公众信心)，需要在多大程度上超越纯粹的经济理由知道什么是最好的。

Real-world studies of host-pathogen dynamics have often failed to keep pace with the development of theoretical concepts. One area where this shortfall is especially regrettable is the application of those concepts in the medical and veterinary sciences. A specific example is the development of predictive models of times and/or locations of high risk of a disease being passed from a wildlife reservoir to human (or domestic animal) populations / so-called zoonotic diseases. This would be the subject of this workshop. A rare example of a model predicting zoonotic outbreaks used long-term data on bubonic plague in Kazakhstan. There, and throughout much of Central Asia, where plague remains a considerable public health concern, the main reservoir host is the great gerbil, Rhombomys opimus. That study demonstrated the existence of a 'critical abundance threshold' in the gerbils, which had to be exceeded for plague to become established in its reservoir (and be a threat), Furthermore, because it was based on past gerbil abundances, the model was not only descriptive but could also be used to predict future outbreaks, i.e. an early warning system. Subsequently, the output from that model has been used to develop a predictive 'expert system' which is being piloted by public health workers in Kazakhstan. The purpose of the proposed workshop is to use the plague model as a springboard to ask (i) What are the prospects of, and what data will be necessary for, utilising critical abundance thresholds, and other key concepts, in developing early warning models for other disease systems in wildlife that are a threat to public health? Indeed, how widely applicable are simple 'threshold' models likely to be? Under what circumstances would different (types of) models be necessary? (ii) How best can such models be turned into tools that are useful to public health practitioners? What do public health workers want/need? Does this differ between the developed and the developing world, and if so how? (iii) How best can predictions such as these be incorporated into a larger risk analysis and/or cost-benefit analysis? 'Ecological' models / at best / generate a probability (with confidence attached) that a disease will be present at a particular place at a particular time. But what is the best way to incorporate the costs of inaction if the disease appears and action has not been taken? Likewise the costs of action that turns out to be unnecessary? And to what extent is it necessary to go beyond knowing what is optimal on purely economic grounds in order to take 'social' factors into account (e.g. loss of public confidence following an untreated outbreak).