Brady Oliver, Wilder-Smith Annelies
Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, UK.
Curr Infect Dis Rep. 2021;23(2):2. doi: 10.1007/s11908-020-00744-9. Epub 2021 Jan 21.
Societal lockdowns in response to the COVID-19 pandemic have led to unprecedented disruption to daily life across the globe. A collateral effect of these lockdowns may be a change to transmission dynamics of a wide range of infectious diseases that are all highly dependent on rates of contact between humans. With timing, duration and intensity of lockdowns varying country-to-country, the wave of lockdowns in 2020 present a unique opportunity to observe how changes in human contact rates, disease control and surveillance affect dengue virus transmission in a global natural experiment. We explore the theoretical basis for the impact of lockdowns on dengue transmission and surveillance then summarise the current evidence base from country reports.
We find considerable variation in the intensity of dengue epidemics reported so far in 2020 with some countries experiencing historic low levels of transmission while others are seeing record outbreaks. Despite many studies warning of the risks of lockdown for dengue transmission, few empirically quantify the impact and issues such as the specific timing of the lockdowns and multi-annual cycles of dengue are not accounted for. In the few studies where such issues have been accounted for, the impact of lockdowns on dengue appears to be limited.
Studying the impact of lockdowns on dengue transmission is important both in how we deal with the immediate COVID-19 and dengue crisis, but also over the coming years in the post-pandemic recovery period. It is clear lockdowns have had very different impacts in different settings. Further analyses might ultimately allow this unique natural experiment to provide insights into how to better control dengue that will ultimately lead to better long-term control.
为应对新冠疫情而实施的社会封锁给全球日常生活带来了前所未有的破坏。这些封锁的一个附带影响可能是改变多种传染病的传播动态，而这些传染病都高度依赖人际接触率。由于各国封锁的时间、持续时间和强度各不相同，2020年的封锁浪潮提供了一个独特的机会，可在全球自然实验中观察人际接触率、疾病控制和监测的变化如何影响登革病毒传播。我们探讨了封锁对登革热传播和监测影响的理论基础，然后总结了各国报告中的现有证据。
我们发现，2020年迄今报告的登革热疫情强度差异很大，一些国家的传播水平处于历史低位，而另一些国家则出现了创纪录的疫情爆发。尽管许多研究警告了封锁对登革热传播的风险，但很少有实证研究量化其影响，且未考虑封锁的具体时间和登革热的多年周期等问题。在少数考虑了这些问题的研究中，封锁对登革热的影响似乎有限。
研究封锁对登革热传播的影响，不仅对我们应对当前的新冠疫情和登革热危机很重要，而且在未来几年的疫情后恢复期也很重要。很明显，封锁在不同环境中产生了非常不同的影响。进一步的分析最终可能会让这个独特的自然实验为如何更好地控制登革热提供见解，最终实现更好的长期控制。
