After the honeymoon, the divorce: Unexpected outcomes of disease control measures against endemic infections.
After the honeymoon, the divorce: Unexpected outcomes of disease control measures against endemic infections.
复制标题
DOI：
10.1371/journal.pcbi.1008292
复制
发表时间：
2020-10
影响因子：
4.3
通讯作者：
Lloyd AL
中科院分区：
文献类型：
--
作者：
Hollingsworth B;Okamoto KW;Lloyd AL
许多地方病缺乏有效的疫苗，往往迫使政策制定者依靠病媒控制等非免疫控制措施来减轻这些疾病的巨大负担。众所周知，控制措施可能对地方性感染产生违反直觉的影响，包括蜜月效应，即部分有效的控制措施不仅会导致感染的初始减少量超出预期，而且会在控制期间因易感者的积累而导致大规模爆发。不幸的是，许多控制措施不能无限期地维持，而且人们对停止的结果知之甚少。在这里，我们检查了流行地区停止或失败的非免疫控制措施的结果。通过使用数学模型比较有控制和无控制的预期累计病例数，我们发现，从控制开始的时间算起，部署控制可以导致比没有任何控制更多的感染总数，即离婚效应。这一结果与非免疫对照导致的人群水平免疫力丧失直接相关，并且在使用非免疫对照来对抗赋予免疫力的感染时的各种模型中都可以看到这一结果。最后，我们研究了三种控制计划，以尽量减少季节性感染中离婚效应的程度，并表明它们无法消除离婚效应。虽然我们不建议停止依赖非免疫控制的控制计划，但我们的结果强烈认为，当不太可能无限期使用控制措施时，在针对地方性感染部署此类控制措施之前应考虑易感性的积累。我们强调，我们的结果与地方性蚊媒感染（例如登革热病毒）特别密切，无论是对于涉及病媒控制的常规管理还是新型控制方法的现场试验，以及针对 COVID-19 的非药物干预措施。许多常见的地方性感染缺乏有效、廉价的疫苗接种，控制依赖于减少传播，例如通过疫苗接种。减少登革热的蚊子数量。通常，使用这些控制措施的直接目标是减少当前发生率，而不太重视稍后会发生什么，更不用说控制停止后会发生什么了。在这里，通过观察自控制期开始以来的累积发病率，而不是瞬时发病率，我们表明，当控制停止或失败时，由此产生的疫情可能足够大，足以完全消除控制的任何好处。我们将这种结果称为离婚效应。此外，我们表明，这一结果并不限于特定的传播途径或流行病学参数，而是与非免疫对照中固有的群体免疫力的降低直接相关。最后，通过评估最小化离婚效应程度的计划，我们表明，如果不维持群体免疫力，或成功地持续控制数十年，就不可能使控制后疫情的成本超过控制计划的收益。我们注意到，我们的结果在针对 COVID-19 的非药物干预措施中具有重要意义。
The lack of effective vaccines for many endemic diseases often forces policymakers to rely on non-immunizing control measures, such as vector control, to reduce the massive burden of these diseases. Controls can have well-known counterintuitive effects on endemic infections, including the honeymoon effect, in which partially effective controls cause not only a greater initial reduction in infection than expected, but also large outbreaks during control resulting from accumulation of susceptibles. Unfortunately, many control measures cannot be maintained indefinitely, and the results of cessation are poorly understood. Here, we examine the results of stopped or failed non-immunizing control measures in endemic settings. By using a mathematical model to compare the cumulative number of cases expected with and without control, we show that deployment of control can lead to a larger total number of infections, counting from the time that control started, than without any control–the divorce effect. This result is directly related to the population-level loss of immunity resulting from non-immunizing controls and is seen in a variety of models when non-immunizing controls are used against an infection that confers immunity. Finally, we examine three control plans for minimizing the magnitude of the divorce effect in seasonal infections and show that they are incapable of eliminating the divorce effect. While we do not suggest stopping control programs that rely on non-immunizing controls, our results strongly argue that the accumulation of susceptibility should be considered before deploying such controls against endemic infections when indefinite use of the control is unlikely. We highlight that our results are particularly germane to endemic mosquito-borne infections, such as dengue virus, both for routine management involving vector control and for field trials of novel control approaches, and in the context of non-pharmaceutical interventions aimed at COVID-19. Many common endemic infections lack effective, inexpensive vaccinations, and control relies instead on transmission reduction, e.g. mosquito population reduction for dengue. Often, these controls are used with the immediate goal of decreasing the current incidence with little importance placed on what will happen at later points in time, and much less what will happen once the control is stopped. Here, by looking at the cumulative incidence since the beginning of the control period, instead of the instantaneous incidence, we show that when controls are stopped, or fail, the resulting outbreaks can be large enough to completely eliminate any benefit of the control. We call this result the divorce effect. Further, we show that this result is not limited to specific transmission pathways or epidemiological parameters, but is instead tied directly to the reduction of herd immunity inherent in non-immunizing controls. Lastly, by evaluating programs to minimize the magnitude of the divorce effect, we show that without maintaining herd immunity, or successfully continuing control for decades, it is impossible to keep the costs of post-control outbreaks from outweighing the benefits of the control program. We note that our results have significance in the context of non-pharmaceutical interventions aimed at COVID-19.
登录
查看更多内容
DOI：
10.1126/science.aaa4339
发表时间：
2015-03-13
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Heesterbeek H;Anderson RM;Andreasen V;Bansal S;De Angelis D;Dye C;Eames KT;Edmunds WJ;Frost SD;Funk S;Hollingsworth TD;House T;Isham V;Klepac P;Lessler J;Lloyd-Smith JO;Metcalf CJ;Mollison D;Pellis L;Pulliam JR;Roberts MG;Viboud C;Isaac Newton Institute IDD Collaboration
通讯作者：
Isaac Newton Institute IDD Collaboration
影响因子：
3.5
作者：
Bacaer, Nicolas;Gomes, M. Gabriela M.
通讯作者：
Gomes, M. Gabriela M.
影响因子：
3.8
作者：
Hladish TJ;Pearson CAB;Patricia Rojas D;Gomez-Dantes H;Halloran ME;Vazquez-Prokopec GM;Longini IM
通讯作者：
Longini IM
影响因子：
8.8
作者：
Mordecai, Erin A.;Paaijmans, Krijn P.;Lafferty, Kevin D.
通讯作者：
Lafferty, Kevin D.
DOI：
10.1016/s0140-6736(17)32130-x
发表时间：
2017-09-16
期刊：
Lancet (London, England)
影响因子：
--
作者：
GBD 2016 DALYs and HALE Collaborators
通讯作者：
GBD 2016 DALYs and HALE Collaborators