The most important features to assess the severity of an epidemic are its size and its timescale. We discuss these features in a systematic way in the context of SIR and SIR-type models. We investigate in detail how the size and timescale of the epidemic can be changed by acting on the parameters characterizing the model. Using these results and having as guideline the COVID-19 epidemic in Italy, we compare the efficiency of different containment strategies for contrasting an epidemic diffusion such as social distancing, lockdown, tracing, early detection and isolation.

中文翻译：

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SIR 框架中流行病的规模和时间范围。

评估流行病严重程度的最重要特征是其规模和时间范围。我们在 SIR 和 SIR 型模型的背景下系统地讨论这些特征。我们详细研究了如何通过作用于表征模型的参数来改变流行病的规模和时间尺度。使用这些结果并以意大利的 COVID-19 疫情为指导，我们比较了不同遏制策略的效率，以对比流行病的扩散，例如社交距离、封锁、追踪、早期发现和隔离。