Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, Imperial College London, St Mary's Campus, London, W2 1PG, UK.
Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, Imperial College London, St Mary's Campus, London, W2 1PG, UK.
Parasit Vectors. 2017 Feb 9;10(1):73. doi: 10.1186/s13071-017-1988-9.
The pork tapeworm, Taenia solium, and associated human infections, taeniasis, cysticercosis and neurocysticercosis, are serious public health problems, especially in developing countries. The World Health Organization (WHO) has set goals for having a validated strategy for control and elimination of T. solium taeniasis/cysticercosis by 2015 and interventions scaled-up in selected countries by 2020. Timely achievement of these internationally-endorsed targets requires that the relative benefits and effectiveness of potential interventions be explored rigorously within a quantitative framework.
A deterministic, compartmental transmission model (EPICYST) was developed to capture the dynamics of the taeniasis/cysticercosis disease system in the human and pig hosts. Cysticercosis prevalence in humans, an outcome of high epidemiological and clinical importance, was explicitly modelled. A next generation matrix approach was used to derive an expression for the basic reproduction number, R . A full sensitivity analysis was performed using a methodology based on Latin-hypercube sampling partial rank correlation coefficient index.
EPICYST outputs indicate that chemotherapeutic intervention targeted at humans or pigs would be highly effective at reducing taeniasis and cysticercosis prevalence when applied singly, with annual chemotherapy of humans and pigs resulting, respectively, in 94 and 74% of human cysticercosis cases averted. Improved sanitation, meat inspection and animal husbandry are less effective but are still able to reduce prevalence singly or in combination. The value of R for taeniasis was estimated at 1.4 (95% Credible Interval: 0.5-3.6).
Human- and pig-targeted drug-focussed interventions appear to be the most efficacious approach from the options currently available. The model presented is a forward step towards developing an informed control and elimination strategy for cysticercosis. Together with its validation against field data, EPICYST will be a valuable tool to help reach the WHO goals and to conduct economic evaluations of interventions in varying epidemiological settings.
猪肉绦虫（Taenia solium）及其相关的人类感染，带绦虫病、囊尾蚴病和脑囊尾蚴病，是严重的公共卫生问题，尤其是在发展中国家。世界卫生组织（WHO）已制定目标，争取到 2015 年制定出经证实有效的猪肉绦虫病/囊尾蚴病控制和消除战略，并在 2020 年之前在选定的国家扩大干预措施。要及时实现这些国际认可的目标，就需要在定量框架内严格探讨潜在干预措施的相对效益和有效性。
我们开发了一个确定性、隔室传播模型（EPICYST），以捕捉人类和猪宿主中带绦虫病/囊尾蚴病疾病系统的动态。明确建模了人类囊尾蚴病的流行率，这是一个具有高度流行病学和临床重要性的结果。采用下一代矩阵方法推导出基本繁殖数 R 的表达式。采用基于拉丁超立方抽样偏秩相关系数指数的方法进行了全面的敏感性分析。
EPICYST 的输出结果表明，单独针对人类或猪进行化学治疗干预，对于降低带绦虫病和囊尾蚴病的流行率将非常有效，人类和猪的年度化疗分别可使 94%和 74%的人类囊尾蚴病病例得到预防。改善卫生、肉类检验和畜牧业虽然效果较差，但仍能单独或联合降低流行率。带绦虫病的 R 值估计为 1.4（95%可信区间：0.5-3.6）。
针对人类和猪的药物为重点的干预措施似乎是目前可用方案中最有效的方法。所提出的模型是朝着制定囊尾蚴病知情控制和消除策略迈出的一步。与针对实地数据的验证一起，EPICYST 将成为一种有价值的工具，有助于实现世卫组织的目标，并在不同的流行病学环境中对干预措施进行经济评估。
