Brunton Lucy A, Donnelly Christl A, O'Connor Heather, Prosser Alison, Ashfield Stuart, Ashton Adam, Upton Paul, Mitchell Andrew, Goodchild Anthony V, Parry Jessica E, Downs Sara H
Department of Epidemiological Sciences Animal and Plant Health Agency Addlestone UK.
Department of Infectious Disease Epidemiology Faculty of Medicine School of Public Health Imperial College London MRC Centre for Outbreak Analysis and Modelling London UK.
Ecol Evol. 2017 Aug 4;7(18):7213-7230. doi: 10.1002/ece3.3254. eCollection 2017 Sep.
Culling badgers to control the transmission of bovine tuberculosis (TB) between this wildlife reservoir and cattle has been widely debated. Industry-led culling began in Somerset and Gloucestershire between August and November 2013 to reduce local badger populations. Industry-led culling is not designed to be a randomized and controlled trial of the impact of culling on cattle incidence. Nevertheless, it is important to monitor the effects of the culling and, taking the study limitations into account, perform a cautious evaluation of the impacts. A standardized method for selecting areas matched to culling areas in factors found to affect cattle TB risk has been developed to evaluate the impact of badger culling on cattle TB incidence. The association between cattle TB incidence and badger culling in the first 2 years has been assessed. Descriptive analyses without controlling for confounding showed no association between culling and TB incidence for Somerset, or for either of the buffer areas for the first 2 years since culling began. A weak association was observed in Gloucestershire for Year 1 only. Multivariable analysis adjusting for confounding factors showed that reductions in TB incidence were associated with culling in the first 2 years in both the Somerset and Gloucestershire intervention areas when compared to areas with no culling (incidence rate ratio (IRR): 0.79, 95% CI: 0.72-0.87, < .001 and IRR: 0.42, 95% CI: 0.34-0.51, < .001, respectively). An increase in incidence was associated with culling in the 2-km buffer surrounding the Somerset intervention area (IRR: 1.38, 95% CI: 1.09-1.75, = .008), but not in Gloucestershire (IRR: 0.91, 95% CI: 0.77-1.07, = .243). As only 2 intervention areas with 2 years of data are available for analysis, and the biological cause-effect relationship behind the statistical associations is difficult to determine, it would be unwise to use these findings to develop generalizable inferences about the effectiveness of the policy at present.
捕杀獾以控制牛结核病（TB）在这种野生动物宿主与牛群之间的传播一直存在广泛争议。由行业主导的捕杀于2013年8月至11月在萨默塞特郡和格洛斯特郡开始，以减少当地獾的数量。由行业主导的捕杀并非旨在成为一项关于捕杀对牛发病率影响的随机对照试验。然而，监测捕杀的效果并在考虑研究局限性的情况下对其影响进行谨慎评估很重要。已开发出一种标准化方法，用于选择在发现影响牛结核病风险的因素方面与捕杀区域相匹配的区域，以评估獾捕杀对牛结核病发病率的影响。已评估了前两年牛结核病发病率与獾捕杀之间的关联。在不控制混杂因素的描述性分析中，对于萨默塞特郡，或者在捕杀开始后的头两年里，对于任何一个缓冲区，捕杀与结核病发病率之间均未显示出关联。仅在格洛斯特郡的第一年观察到微弱关联。在对混杂因素进行调整的多变量分析中，与未进行捕杀的区域相比，在萨默塞特郡和格洛斯特郡的干预区域，前两年结核病发病率的降低与捕杀有关（发病率比（IRR）：0.79，95%置信区间：0.72 - 0.87，< 0.001；IRR：0.42，95%置信区间：0.34 - 0.51，< 0.001）。在萨默塞特郡干预区域周围2公里的缓冲区，发病率的增加与捕杀有关（IRR：1.38，95%置信区间：1.09 - 1.75，P = 0.008），但在格洛斯特郡则不然（IRR：0.91，95%置信区间：0.77 - 1.07，P = 0.243）。由于仅有两个有两年数据的干预区域可供分析，并且统计关联背后的生物学因果关系难以确定，目前利用这些发现得出关于该政策有效性的可推广推论是不明智的。
