Centre for Emerging, Endemic and Exotic Diseases (CEEED), Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, AL9 7TA, UK.
Prev Vet Med. 2011 Apr 1;99(1):4-14. doi: 10.1016/j.prevetmed.2011.01.001. Epub 2011 Feb 3.
In the absence of data, qualitative risk assessment frameworks have proved useful to assess risks associated with animal health diseases. As part of a scientific opinion for the European Commission (EC) on African Swine Fever (ASF), a working group of the European Food Safety Authority (EFSA) assessed the risk of ASF remaining endemic in Trans Caucasus Countries (TCC) and the Russian Federation (RF) and the risk of ASF becoming endemic in the EU if disease were introduced. The aim was to develop a tool to evaluate how current control or preventive measures mitigate the risk of spread and giving decision makers the means to review how strengthening of surveillance and control measures would mitigate the risk of disease spread. Based on a generic model outlining disease introduction, spread and endemicity in a region, the impact of risk mitigation measures on spread of disease was assessed for specific risk questions. The resulting hierarchical models consisted of key steps containing several sub-steps. For each step of the risk pathways risk estimates were determined by the expert group based on existing data or through expert opinion elicitation. Risk estimates were combined using two different combination matrices, one to combine estimates of independent steps and one to combine conditional probabilities. The qualitative risk assessment indicated a moderate risk that ASF will remain endemic in current affected areas in the TCC and RF and a high risk of spread to currently unaffected areas. If introduced into the EU, ASF is likely to be controlled effectively in the production sector with high or limited biosecurity. In the free range production sector, however, there is a moderate risk of ASF becoming endemic due to wild boar contact, non-compliance with animal movement bans, and difficult access to all individual pigs upon implementation of control measures. This study demonstrated the advantages of a systematic framework to assist an expert panel to carry out a risk assessment as it helped experts to disassociate steps in the risk pathway and to overcome preconceived notions of final risk estimates. The approach presented here shows how a qualitative risk assessment framework can address animal diseases with complexity in their spread and control measures and how transparency of the resulting estimates was achieved.
在缺乏数据的情况下，定性风险评估框架已被证明可用于评估与动物健康疾病相关的风险。作为欧洲食品安全局 (EFSA) 为欧盟委员会 (EC) 编写的关于非洲猪瘟 (ASF) 的科学意见的一部分，EFSA 的一个工作组评估了 ASF 在南高加索国家 (TCC) 和俄罗斯联邦 (RF) 持续流行的风险，如果疾病传入欧盟，ASF 在欧盟流行的风险。目的是开发一种工具来评估当前的控制或预防措施如何减轻传播风险，并为决策者提供手段来审查加强监测和控制措施将如何减轻疾病传播的风险。基于概述区域内疾病传入、传播和流行的通用模型，针对特定风险问题评估了减轻风险措施对疾病传播的影响。基于专家小组对现有数据或通过专家意见征询来确定风险缓解措施对疾病传播风险的影响。风险估计是通过专家小组基于现有数据或通过专家意见征询来确定的。风险估计使用两种不同的组合矩阵进行组合，一种用于组合独立步骤的估计值，另一种用于组合条件概率。定性风险评估表明，ASF 在 TCC 和 RF 目前受影响地区持续流行的风险中等，传播到目前未受影响地区的风险很高。如果传入欧盟，ASF 在生产部门很可能得到有效控制，因为这些部门具有较高或有限的生物安全水平。然而，在自由放养生产部门，由于野猪接触、不遵守动物移动禁令以及在实施控制措施时难以接触到所有个体猪，ASF 流行的风险中等。本研究展示了系统框架的优势，该框架有助于专家小组进行风险评估，因为它帮助专家们将风险途径中的步骤分开，并克服对最终风险估计的先入为主的观念。本文提出的方法展示了定性风险评估框架如何解决传播和控制措施复杂的动物疾病，以及如何实现结果估计的透明度。
