We provide a SEIR epidemic model for the spread of COVID-19 using the Caputo fractional derivative. The feasibility region of the system and equilibrium points are calculated and the stability of the equilibrium points is investigated. We prove the existence of a unique solution for the model by using fixed point theory. Using the fractional Euler method, we get an approximate solution to the model. To predict the transmission of COVID-19 in Iran and in the world, we provide a numerical simulation based on real data.

中文翻译：

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通过分数阶 Caputo 导数构建的 COVID-19 传播 SEIR 流行病模型。

我们使用 Caputo 分数阶导数提供了针对 COVID-19 传播的 SEIR 流行病模型。计算了系统的可行域和平衡点，并考察了平衡点的稳定性。我们利用不动点理论证明了模型唯一解的存在性。使用分数欧拉方法，我们得到模型的近似解。为了预测 COVID-19 在伊朗和世界范围内的传播，我们提供了基于真实数据的数值模拟。