21-ICRAD: Tackling chronic wasting disease in Europe

慢性消耗性疾病（CWD）是一种影响鹿的朊病毒疾病，类似于疯牛病或牛的“疯牛病”。与疯牛病不同的是，目前还没有证据表明它可以传播给人类，但它已经在北美的野生和养殖鹿中非常普遍，对某些地区的种群数量产生了重大影响。2016年，CWD首次在欧洲挪威的一头野生驯鹿身上被发现，此后在挪威及其邻国的驯鹿、驼鹿和马鹿中发现了更多病例。从这些病例中发现的朊病毒的特征与在北美发现的明显不同，表明它们不是由CWD输入引起的。欧洲和北美在野鹿的种类、种群规模和分布、栖息地和管理方面也存在重大差异。这些差异意味着从北美CWD的经验中吸取的教训不一定适用于欧洲的疾病控制规划。该研究项目将填补我们知识上的空白，目的是开发有针对性和具有成本效益的方法来检测CWD并限制其在欧洲鹿群中的传播。我们将利用有关挪威和瑞典CWD病例以及这些国家鹿群的信息，开发数学工具，帮助决定在何处指导疾病检测工作，并预测疾病的传播，从而制定和检验控制战略。如果将来发现CWD，这些工具可以在其他欧洲国家进行调整和应用。我们还将评估在欧洲的任何主要野生和养殖鹿品种中是否存在对CWD的遗传抗性，因为选择性育种抗病可能有助于控制或预防传播。最后，我们将研究欧洲CWD菌株传播给家畜（例如羊、牛和猪）或人的可能性，方法是通过实验感染经过基因改造以模仿每种物种的朊病毒敏感性的小鼠，以及其他实验室方法。从事这一项目的研究联盟汇集了从事动物和人类朊病毒疾病研究的欧洲主要研究小组的专门知识和资源。该项目的成果将提供关于欧洲慢性腹泻病潜在影响的证据，这对于了解该病的风险和规划有效方法以控制和预防该病对动物、人类和环境健康的不利影响至关重要。

Chronic wasting disease (CWD) is a prion disease that affects deer, similar to BSE or "mad cow disease" of cattle. Unlike BSE, there is as yet no evidence that it can spread to humans, but it has become very widespread in wild and farmed deer across North America, with major impacts on population numbers in some areas. In 2016, CWD was found for the first time in Europe, in a wild reindeer in Norway, and since then more cases have been found in reindeer, moose and red deer in Norway and neighbouring countries. The characteristics of the prions from these cases are distinctly different from those found in North America, suggesting that they have not arisen from importation of CWD. There are also major differences between Europe and North America in the species of wild deer, their population sizes and distribution, habitat and management. These differences mean that lessons learned from the experience of CWD in North America do not necessarily apply when planning control of the disease in Europe. This research project will address gaps in our knowledge, with the aim of developing targeted and cost-effective ways to detect CWD and limit its spread within European deer populations. We will use information about CWD cases in Norway and Sweden and deer populations in these countries to develop mathematical tools that help decisions about where to direct disease detection efforts, and predict the spread of the disease, so that control strategies can be devised and tested. These tools can be adapted and applied in other European countries if CWD is found there in future. We will also assess whether there is genetic resistance to CWD among any of the major breeds of wild and farmed deer in Europe, since selective breeding for disease resistance may help in control or prevention of spread. Finally, we will examine the likelihood that European CWD strains could spread to farmed livestock (e.g. sheep, cattle and pigs) or people, by experimental infection of mice that have been genetically altered to mimic the prion susceptibility of each species, as well as alternative laboratory methods. The research consortium working on this project brings together expertise and resources from leading European research groups working on animal and human prion diseases. The outcomes of the project will provide evidence on the potential impacts of CWD in Europe, which will be vital in understanding the risks and planning effective ways to control and prevent adverse effects of the disease on animal, human and environmental health.