Centre for Complexity Science, Zeeman Building, University of Warwick, Coventry, CV4 7AL, UK.
Prev Vet Med. 2012 May 1;104(3-4):224-39. doi: 10.1016/j.prevetmed.2011.11.007. Epub 2011 Dec 12.
In this paper, we simulate outbreaks of foot-and-mouth disease in the Commonwealth of Pennsylvania, USA - after the introduction of a state-wide movement ban - as they might unfold in the presence of mitigation strategies. We have adapted a model previously used to investigate FMD control policies in the UK to examine the potential for disease spread given an infection seeded in each county in Pennsylvania. The results are highly dependent upon the county of introduction and the spatial scale of transmission. Should the transmission kernel be identical to that for the UK, the epidemic impact is limited to fewer than 20 premises, regardless of the county of introduction. However, for wider kernels where infection can spread further, outbreaks seeded in or near the county with highest density of premises and animals result in large epidemics (>150 premises). Ring culling and vaccination reduce epidemic size, with the optimal radius of the rings being dependent upon the county of introduction. Should the kernel width exceed a given county-dependent threshold, ring culling is unable to control the epidemic. We find that a vaccinate-to-live policy is generally preferred to ring culling (in terms of reducing the overall number of premises culled), indicating that well-targeted control can dramatically reduce the risk of large scale outbreaks of foot-and-mouth disease occurring in Pennsylvania.
在本文中，我们模拟了美国宾夕法尼亚州在全州范围内实施移动禁令后，可能出现的口蹄疫爆发情况——考虑到缓解策略的存在。我们改编了一个之前用于调查英国口蹄疫控制政策的模型，以研究在宾夕法尼亚州每个县播种感染的情况下疾病传播的可能性。结果高度依赖于传入县和传播的空间尺度。如果传输核与英国的相同，那么无论传入县如何，疫情的影响都将仅限于不到 20 个场所。然而，对于更广泛的核，感染可以传播得更远，在场所和动物密度最高的县或附近播种的爆发会导致大规模疫情（超过 150 个场所）。环形扑杀和疫苗接种可减少疫情规模，环的最佳半径取决于传入县。如果核宽度超过给定的县相关阈值，则环形扑杀无法控制疫情。我们发现，一般来说，接种疫苗以维持生命的政策优于环形扑杀（从减少被扑杀的场所总数来看），这表明目标明确的控制可以显著降低宾夕法尼亚州发生大规模口蹄疫爆发的风险。
