Department of Social Sciences, Business Economics, Wageningen University, Hollandseweg 1, NL-6706 KN Wageningen, The Netherlands.
Department of Social Sciences, Business Economics, Wageningen University, Hollandseweg 1, NL-6706 KN Wageningen, The Netherlands.
Prev Vet Med. 2014 Aug 1;115(3-4):75-87. doi: 10.1016/j.prevetmed.2014.03.027. Epub 2014 Apr 4.
In order to put a halt to the Bluetongue virus serotype 8 (BTV-8) epidemic in 2008, the European Commission promoted vaccination at a transnational level as a new measure to combat BTV-8. Most European member states opted for a mandatory vaccination campaign, whereas the Netherlands, amongst others, opted for a voluntary campaign. For the latter to be effective, the farmer's willingness to vaccinate should be high enough to reach satisfactory vaccination coverage to stop the spread of the disease. This study looked at a farmer's expected utility of vaccination, which is expected to have a positive impact on the willingness to vaccinate. Decision analysis was used to structure the vaccination decision problem into decisions, events and payoffs, and to define the relationships among these elements. Two scenarios were formulated to distinguish farmers' mindsets, based on differences in dairy heifer management. For each of the scenarios, a decision tree was run for two years to study vaccination behaviour over time. The analysis was done based on the expected utility criterion. This allows to account for the effect of a farmer's risk preference on the vaccination decision. Probabilities were estimated by experts, payoffs were based on an earlier published study. According to the results of the simulation, the farmer decided initially to vaccinate against BTV-8 as the net expected utility of vaccination was positive. Re-vaccination was uncertain due to less expected costs of a continued outbreak. A risk averse farmer in this respect is more likely to re-vaccinate. When heifers were retained for export on the farm, the net expected utility of vaccination was found to be generally larger and thus was re-vaccination more likely to happen. For future animal health programmes that rely on a voluntary approach, results show that the provision of financial incentives can be adjusted to the farmers' willingness to vaccinate over time. Important in this respect are the decision moment and the characteristics of the disease. Farmers' perceptions of the disease risk and about the efficacy of available control options cannot be neglected.
为了阻止 2008 年的蓝舌病毒血清 8 型（BTV-8）流行，欧盟在跨国层面推动接种疫苗，将其作为防治 BTV-8 的一项新措施。大多数欧洲成员国选择实施强制性疫苗接种运动，而荷兰等国家则选择实施自愿性疫苗接种运动。为了使后者有效，农民接种疫苗的意愿应足够高，以达到令人满意的疫苗接种覆盖率，从而阻止疾病的传播。本研究着眼于农民对疫苗接种的预期效用，这有望对接种意愿产生积极影响。决策分析用于将疫苗接种决策问题构建为决策、事件和收益，并定义这些要素之间的关系。基于奶牛后备牛管理的差异，制定了两种方案来区分农民的思维模式。对于每种方案，都运行了一个为期两年的决策树来研究随时间推移的疫苗接种行为。分析是基于预期效用标准进行的。这允许考虑农民风险偏好对疫苗接种决策的影响。概率由专家估计，收益基于之前发表的一项研究。根据模拟结果，农民最初决定接种 BTV-8，因为接种的净预期效用为正。由于持续爆发的预期成本较低，重新接种是不确定的。在这方面，风险厌恶的农民更有可能重新接种。当后备牛在农场被保留用于出口时，接种的净预期效用通常更大，因此更有可能重新接种。对于依赖自愿接种方法的未来动物健康计划，结果表明，可以根据农民随时间变化的接种意愿调整财政激励措施。在这方面，决策时刻和疾病的特征很重要。农民对疾病风险的看法以及对现有控制选择的效果的看法不容忽视。
