SARS-CoV-2 has now infected 15 million people and produced more than six hundred thousand deaths around the world. Due to high transmission levels, many governments implemented social distancing and confinement measures with different levels of required compliance to mitigate the COVID-19 epidemic. In several countries, these measures were effective, and it was possible to flatten the epidemic curve and control it. In others, this objective was not or has not been achieved. In far too many cities around the world, rebounds of the epidemic are occurring or, in others, plateaulike states have appeared, where high incidence rates remain constant for relatively long periods of time. Nonetheless, faced with the challenge of urgent social need to reactivate their economies, many countries have decided to lift mitigation measures at times of high incidence. In this paper, we use a mathematical model to characterize the impact of short duration transmission events within the confinement period previous but close to the epidemic peak. The model also describes the possible consequences on the disease dynamics after mitigation measures are lifted. We use Mexico City as a case study. The results show that events of high mobility may produce either a later higher peak, a long plateau with relatively constant but high incidence or the same peak as in the original baseline epidemic curve, but with a post-peak interval of slower decay. Finally, we also show the importance of carefully timing the lifting of mitigation measures. If this occurs during a period of high incidence, then the disease transmission will rapidly increase, unless the effective contact rate keeps decreasing, which will be very difficult to achieve once the population is released.

中文翻译：

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解除流动性限制和超级传播事件对COVID-19短期动力学的影响

SARS-CoV-2现在已感染1500万人，在世界各地造成60万人死亡。由于高传播水平，许多政府实施了社会疏离和隔离措施，并按不同级别要求遵守法规，以缓解COVID-19流行病。在一些国家，这些措施是有效的，有可能使流行曲线趋于平坦并加以控制。在另一些国家，这个目标没有实现或没有实现。在世界上太多的城市中，流行病的反弹正在发生，或者在其他城市中出现了高原状的州，这些州的高发病率在相当长的一段时间内保持不变。尽管如此，面对迫切的社会需求以恢复其经济活力的挑战，许多国家已经决定在发生率高的时候取消缓解措施。在本文中，我们使用数学模型来表征短期传播事件在先前的限制期内但接近流行高峰的影响。该模型还描述了取消缓解措施后可能对疾病动态产生的影响。我们以墨西哥城为例。结果表明，高迁移率的事件可能会产生一个更高的峰值，一个较长的平台，具有相对恒定但较高的发病率，或与原始基线流行曲线相同的峰值，但峰后间隔较慢。最后，我们还显示了谨慎安排缓解措施的时机的重要性。如果在高发期间发生这种情况，