Miller Ezer, Dushoff Jonathan, Huppert Amit
The Biostatistics Unit, Gertner Institute for Epidemiology and Health Policy Research, Tel Hashomer, Israel Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
Department of Biology, McMaster University, Hamilton, Ontario, Canada.
J R Soc Interface. 2016 Feb;13(115):20150666. doi: 10.1098/rsif.2015.0666.
Personal protection (PP) techniques, such as insecticide-treated nets, repellents and medications, include some of the most important and commonest ways used today to protect individuals from vector-borne infectious diseases. In this study, we explore the possibility that a PP intervention with partial coverage may have the counterintuitive effect of increasing disease burden at the population level, by increasing the biting intensity on the unprotected portion of the population. To this end, we have developed a dynamic model which incorporates parameters that describe the potential effects of PP on vector searching and biting behaviour and calculated its basic reproductive rate, R0. R0 is a well-established threshold of disease risk; the higher R0 is above unity, the stronger the disease onset intensity. When R0 is below unity, the disease is typically unable to persist. The model analysis revealed that partial coverage with popular PP techniques can realistically lead to a substantial increase in the reproductive number. An increase in R0 implies an increase in disease burden and difficulties in eradication efforts within certain parameter regimes. Our findings therefore stress the importance of studying vector behavioural patterns in response to PP interventions for future mitigation of vector-borne diseases.
个人防护（PP）技术，如经杀虫剂处理的蚊帐、驱虫剂和药物，是当今用于保护个人免受媒介传播传染病侵害的一些最重要且最常见的方法。在本研究中，我们探讨了一种可能性，即部分覆盖的个人防护干预措施可能会产生违反直觉的效果，即在人群层面增加疾病负担，因为这会增加媒介对未受保护人群的叮咬强度。为此，我们开发了一个动态模型，该模型纳入了描述个人防护对媒介搜索和叮咬行为潜在影响的参数，并计算了其基本繁殖率R0。R0是一个公认的疾病风险阈值；R0高于1的幅度越大，疾病发病强度就越强。当R0低于1时，疾病通常无法持续存在。模型分析表明，采用常见的个人防护技术进行部分覆盖实际上可能会导致繁殖数大幅增加。R0的增加意味着在某些参数范围内疾病负担增加以及根除工作面临困难。因此，我们的研究结果强调了研究媒介对个人防护干预措施的行为模式对于未来减轻媒介传播疾病的重要性。
