Department of Mathematics and Statistics, University of Ottawa, 585 King Edward Avenue, Ottawa, ON K1N6N5, Canada.
Department of Mathematics and Statistics, and Department of Biology, University of Ottawa, 585 King Edward Avenue, Ottawa, ON K1N6N5, Canada.
Math Biosci. 2018 May;299:127-137. doi: 10.1016/j.mbs.2018.03.015. Epub 2018 Mar 14.
Even though medical intervention measures against HIV transmission are available, the epidemic continues to spread in several sub-Saharan African countries. Empirical studies indicate that many people are unable to implement prevention strategies because of individual factors, such as extreme poverty or lack of education, but also because or relational factors, such as gender-based violence or transactional sex. This phenomenon, known as choice disability, may be such a large obstacle in the effectiveness of medical interventions that several field trials of structural (non-medical) interventions are underway that address these issues. While dynamical-systems models are frequently used to advise management and policy around infectious diseases, they typically assume that individuals are free to make optimal choices. We derive and analyze a novel model where individuals have a certain choice status, based on which they are more or less likely to transmit or receive the infection. Choice status is affected by social interactions. When studying the model in the absence of an infectious disease, we find that structural interventions aimed at raising the status of one group can have the unintended side effect of lowering the status of another group. When combined with an epidemic model, we find that the same structural interventions can even increase the total prevalence of a disease in the population. Our model provides a framework to evaluate the possible effectiveness of structural intervention in an epidemic.
尽管有针对 HIV 传播的医学干预措施，但该传染病仍在撒哈拉以南的几个非洲国家继续蔓延。实证研究表明，许多人无法实施预防策略，这既是因为个人因素，如极端贫困或缺乏教育，也是因为关系因素，如性别暴力或性交易。这种被称为“选择障碍”的现象，可能是医学干预效果的一个巨大障碍，因此正在进行一些针对这些问题的结构性（非医学）干预的现场试验。虽然动力系统模型常用于为传染病的管理和政策提供建议，但它们通常假设个人可以自由做出最佳选择。我们推导出并分析了一个新模型，其中个人具有一定的选择地位，根据该地位，他们更有可能或更不可能传播或感染疾病。选择地位受到社会互动的影响。在没有传染病的情况下研究该模型时，我们发现旨在提高某一群体地位的结构性干预可能会产生意想不到的副作用，降低另一群体的地位。当与传染病模型结合时，我们发现相同的结构性干预甚至会增加人群中疾病的总流行率。我们的模型为评估结构性干预在传染病中的可能效果提供了一个框架。
