Vaccination against foot-and-mouth disease I: Epidemiological consequences
Vaccination against foot-and-mouth disease I: Epidemiological consequences
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DOI：
10.1016/j.prevetmed.2012.05.012
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发表时间：
2012-11-01
影响因子：
2.6
通讯作者：
van Roermund, H. J. W.
中科院分区：
文献类型：
--
作者：
Backer, J. A.;Hagenaars, T. J.;van Roermund, H. J. W.
口蹄疫（FMD）的流行可以对动物福利、经济收入、出口地位和整个社会产生破坏性影响，正如2001年荷兰发生的FMD流行期间所发生的那样。在这次疫情期间，荷兰政府先发制人地扑杀了26万头动物，并将紧急疫苗接种作为首选控制政策。然而，疫苗到活战略此前并未应用，这对有效控制疫情、恢复无口蹄疫状态和最大限度减少经济损失带来了前所未有的挑战。这三个主题涵盖在一个跨学科的模型分析。在这第一部分中，我们评估是否以及如何紧急疫苗接种可以有效地应用于控制口蹄疫流行在荷兰。为此，我们开发了一个随机的基于个体的模型，描述口蹄疫病毒在动物之间和畜群之间的传播，考虑宿主物种（牛，羊和猪）之间的异质性。我们在人口密集的牲畜区（>4个农场/km（2））的研究结果表明，紧急环形接种可以像先发制人的环形扑杀一样迅速阻止流行，而要扑杀的农场总数减少了四分之一。为实现这一减少，需要在被检测农场周围建立更大的控制半径，并相应地建立足够的疫苗接种能力。尽管对于大多数模拟流行病来说，2公里的疫苗接种区是足够的，但荷兰的疫苗接种能力可能会被平均比牛群大10倍的养猪场耗尽。将养猪场排除在疫苗接种范围之外会略微增加疫情，但需要接种疫苗的动物数量会减少一半以上。以小型羊群为模型的业余羊群在传播流行病方面没有发挥重要作用，因此在控制阶段不需要作为目标。在荷兰一个人口稀少的牲畜区，每平方公里约有2个农场，仅扑杀检测到的农场的最低控制策略似乎足以控制疫情。(c)2012 Elsevier B. V.保留所有权利。
An epidemic of foot-and-mouth disease (FMD) can have devastating effects on animal welfare, economic revenues, the export position and society as a whole, as occurred during the 2001 FMD epidemic in the Netherlands. Following the preemptive culling of 260,000 animals during this outbreak, the Dutch government adopted emergency vaccination as preferred control policy. However, a vaccination-to-live strategy has not been applied before, posing unprecedented challenges for effectively controlling the epidemic, regaining FMD-free status and minimizing economic losses. These three topics are covered in an interdisciplinary model analysis. In this first part we evaluate whether and how emergency vaccination can be effectively applied to control FMD epidemics in the Netherlands. For this purpose we develop a stochastic individual-based model that describes FMD virus transmission between animals and between herds, taking heterogeneity between host species (cattle, sheep and pigs) into account. Our results in a densely populated livestock area with >4 farms/km(2) show that emergency ring vaccination can halt the epidemic as rapidly as preemptive ring culling, while the total number of farms to be culled is reduced by a factor of four. To achieve this reduction a larger control radius around detected farms and a corresponding adequate vaccination capacity is needed. Although sufficient for the majority of simulated epidemics with a 2 km vaccination zone, the vaccination capacity available in the Netherlands can be exhausted by pig farms that are on average ten times larger than cattle herds. Excluding pig farms from vaccination slightly increases the epidemic, but more than halves the number of animals to be vaccinated. Hobby flocks - modelled as small-sized sheep flocks - do not play a significant role in propagating the epidemic, and need not be targeted during the control phase. In a more sparsely populated livestock area in the Netherlands with about 2 farms/km(2) the minimal control strategy of culling only detected farms seems sufficient to control an epidemic. (c) 2012 Elsevier B.V. All rights reserved.