Projected Impact of Dengue Vaccination in Yucatan, Mexico
Projected Impact of Dengue Vaccination in Yucatan, Mexico
复制标题
DOI：
10.1371/journal.pntd.0004661
复制
发表时间：
2016-05-01
影响因子：
3.8
通讯作者：
Longini, Ira M.
中科院分区：
文献类型：
--
作者：
Hladish, Thomas J.;Pearson, Carl A. B.;Longini, Ira M.
登革热疫苗很快将成为减少登革热疾病的新工具，但广泛疫苗接种活动的有效性尚未确定。我们开发了一个基于代理的登革热模型，代表墨西哥尤卡坦半岛人和蚊子之间的运动和传播动态，并模拟了各种疫苗场景以评估在这些条件下的有效性。该模型包含尤卡坦半岛人口的详细空间表示，包括 375,000 个家庭和 100,000 个工作场所和学校之间 180 万人的位置和流动。在可能的情况下，我们设计的模型使用具有国际覆盖范围的数据源，以简化其他地区的重新参数化。模拟和分析整合了 35 年的轻度和重症病例数据（包括可用的登革热血清型）、血清流行率调查结果、卫星图像以及气候、人口普查和经济数据。为了拟合未直接由可用数据提供的模型参数，例如疾病报告率和登革热传播参数，我们开发了一个名为 AbcSmc 的参数估计工具包，并已将其公开。将模拟模型与登革热病例数据进行拟合后，我们预测了传播情况并评估了 20 年来几种疫苗接种策略的相对有效性。疫苗功效基于赛诺菲巴斯德疫苗 Dengvaxia 的 III 期试验结果。我们考虑对 2、9 或 16 岁的儿童进行常规疫苗接种，在 30 岁之前进行或不进行一次性补种活动。由于 Dengvaxia 的持久性尚未确定，因此我们考虑使用可赋予持久或减弱免疫力的假设疫苗，并评估使用加强剂量来对抗减弱的情况。我们发现，使用持久疫苗的合理疫苗接种方案可在五年内将登革热年发病率降低多达 80%。然而，如果疫苗效力在接种后减弱，我们发现可能会出现比没有任何疫苗接种时更大的流行病，并且需要疫苗加强剂量来防止这种结果。
Dengue vaccines will soon provide a new tool for reducing dengue disease, but the effectiveness of widespread vaccination campaigns has not yet been determined. We developed an agent-based dengue model representing movement of and transmission dynamics among people and mosquitoes in Yucatan, Mexico, and simulated various vaccine scenarios to evaluate effectiveness under those conditions. This model includes detailed spatial representation of the Yucatan population, including the location and movement of 1.8 million people between 375,000 households and 100,000 workplaces and schools. Where possible, we designed the model to use data sources with international coverage, to simplify reparameterization for other regions. The simulation and analysis integrate 35 years of mild and severe case data (including dengue serotype when available), results of a seroprevalence survey, satellite imagery, and climatological, census, and economic data. To fit model parameters that are not directly informed by available data, such as disease reporting rates and dengue transmission parameters, we developed a parameter estimation toolkit called AbcSmc, which we have made publicly available. After fitting the simulation model to dengue case data, we forecasted transmission and assessed the relative effectiveness of several vaccination strategies over a 20 year period. Vaccine efficacy is based on phase III trial results for the Sanofi-Pasteur vaccine, Dengvaxia. We consider routine vaccination of 2, 9, or 16 year-olds, with and without a one-time catch-up campaign to age 30. Because the durability of Dengvaxia is not yet established, we consider hypothetical vaccines that confer either durable or waning immunity, and we evaluate the use of booster doses to counter waning. We find that plausible vaccination scenarios with a durable vaccine reduce annual dengue incidence by as much as 80% within five years. However, if vaccine efficacy wanes after administration, we find that there can be years with larger epidemics than would occur without any vaccination, and that vaccine booster doses are necessary to prevent this outcome.