In their article, N. A. Kudryashov, M. A. Chmykhov, M. Vigdorowitsch, “Analytical features of the SIR model and their applications to COVID-19”, Applied Mathematical Modelling 90 (2021) 466–473, aimed to establish the relationships among S, I and R populations, as well as to suggest a form for the exact solution of the SIR model. One of the equations given there is not correct, which leads to an error in the solution. The objective of the present letter is to present the correct parametric solution and to discuss its numerical approximation by direct quadrature.

中文翻译：

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关于SIR模型的一些分析和数值方面的评论

在他们的文章中，NA Kudryashov，MA Chmykhov，M。Vigdorowitsch，“ SIR模型的分析特征及其在COVID-19中的应用”，应用数学建模90（2021）466–473，旨在建立S，I之间的关系。和R族，以及为SIR模型的精确解提供一种形式。给定的方程式之一不正确，这会导致解决方案中的错误。本信的目的是提出正确的参数解，并讨论通过直接正交的数值近似。