Bergevoet R H M, van Schaik G, Veling J, Backus G B C, Franken P
Wageningen UR, Agricultural Economics Research Institute, P.O. Box 35, 6700 AA Wageningen, The Netherlands.
Prev Vet Med. 2009 May 1;89(1-2):1-7. doi: 10.1016/j.prevetmed.2008.12.007. Epub 2009 Feb 7.
This paper presents an analysis of a Salmonella control program for Dutch dairy herds. Salmonella control strategies were evaluated using a computer-based model consisting of an epidemiological module and an economics module. The epidemiological module is a state transition model of the infectivity of a herd, with the unit of analysis being the individual farm. The probability of a herd going from one state in the model to another state was derived from biological characteristics of Salmonella infections in dairy herds, and the presence or absence of risk factors. The economics module was based on partial budgeting. Control measures were modeled as influencing the risk factors. Amongst the measures considered were the prohibition of transporting potentially infectious animals and manure to farms, the culling of chronically infected animals, and herd management measures such as separate housing of groups of animal that differ in age. Alternative strategies, both compulsory and obligatory, were defined and evaluated concerning the reduction of prevalence of infected herds, the cost of a strategy, and cost-effectiveness. Results of the model suggested that a compulsory control strategy which included culling chronically infected animals and prohibiting the transport of potentially infected animals reduces the prevalence of Salmonella positive herds considerably, and was most cost-effective. Adding hygienic measures and a ban on the transport of animal manure further reduces prevalence, but only slightly, and with substantially more costs.
本文对荷兰奶牛场的沙门氏菌控制计划进行了分析。利用一个由流行病学模块和经济学模块组成的计算机模型对沙门氏菌控制策略进行了评估。流行病学模块是一个畜群感染性的状态转换模型，分析单位是个体农场。畜群在模型中从一种状态转变为另一种状态的概率源自奶牛场沙门氏菌感染的生物学特征以及风险因素的存在与否。经济学模块基于局部预算编制。控制措施被建模为对风险因素产生影响。所考虑的措施包括禁止将潜在感染动物和粪便运往农场、扑杀慢性感染动物以及诸如将不同年龄组动物分开饲养等畜群管理措施。针对感染畜群患病率的降低、策略成本以及成本效益，定义并评估了强制性和义务性的替代策略。模型结果表明，一项包括扑杀慢性感染动物和禁止运输潜在感染动物的强制性控制策略可大幅降低沙门氏菌阳性畜群的患病率，且成本效益最高。增加卫生措施和禁止运输动物粪便可进一步降低患病率，但降幅很小，且成本大幅增加。
