CHICAS, Lancaster Medical School, Lancaster University, Lancaster, UK.
Epidemiol Infect. 2021 Apr 12;149:e99. doi: 10.1017/S0950268821000753.
Serology data are an increasingly important tool in malaria surveillance, especially in low transmission settings where the estimation of parasite-based indicators is often problematic. Existing methods rely on the use of thresholds to identify seropositive individuals and estimate transmission intensity, while making assumptions about the temporal dynamics of malaria transmission that are rarely questioned. Here, we present a novel threshold-free approach for the analysis of malaria serology data which avoids dichotomization of continuous antibody measurements and allows us to model changes in the antibody distribution across age in a more flexible way. The proposed unified mechanistic model combines the properties of reversible catalytic and antibody acquisition models, and allows for temporally varying boosting and seroconversion rates. Additionally, as an alternative to the unified mechanistic model, we also propose an empirical approach to analysis where modelling of the age-dependency is informed by the data rather than biological assumptions. Using serology data from Western Kenya, we demonstrate both the usefulness and limitations of the novel modelling framework.
血清学数据是疟疾监测中越来越重要的工具,特别是在低传播环境中,寄生虫指标的估计往往存在问题。现有的方法依赖于使用阈值来识别血清阳性个体并估计传播强度,同时对疟疾传播的时间动态做出假设,这些假设很少受到质疑。在这里,我们提出了一种新颖的无阈值方法来分析疟疾血清学数据,该方法避免了将连续抗体测量值二分法,并允许我们以更灵活的方式对年龄相关的抗体分布变化进行建模。所提出的统一机械模型结合了可逆催化和抗体获取模型的特性,并允许随时间变化的增强和血清转化速率。此外,作为对统一机械模型的替代,我们还提出了一种经验方法来分析,其中对年龄相关性的建模是由数据而不是生物学假设来告知的。我们使用来自肯尼亚西部的血清学数据,展示了新的建模框架的有用性和局限性。