The present study investigates essential steps in build‐up of models for description of the spread of infectious diseases. Combining these modules, a SEI³RSD model will be developed, which can take into account a possible passive immunisation by vaccination as well as different durations of latent and incubation periods. Besides, infectious persons with and without symptoms can be distinguished. Due to the current world‐wide SARS‐CoV‐2 pandemic (COVID‐19 pandemic) models for description of the spread of infectious diseases and their application for forecasts have become into the focus of the scientific community as well as of broad public more than usual. Currently, many papers and studies have appeared and appear dealing with the virus SARS‐CoV‐2 and the COVID‐19 disease caused by it. This occurs under medical, virological, economic, sociological and further aspects as well as under mathematical points of view. Concerning the last‐mentioned point, the main focus lies on the application of existing models and their adaptation to data about the course of infection available at the current time. Clearly, the aim is to predict the possible further development, for instance in Germany. It is of particular interest to investigate how will be the influence of political and administrative measures like contact restrictions, closing or rather re‐opening of schools, restaurants, hotels etc. on the course of infection. The steps considered here for building up suitable models are well‐known for long time. However, understandably they will not be dealt with in an extended way in current application‐oriented works. Therefore, it is the aim of this study to present some existing steps of modelling without any pretension of completeness. Thus, on the one hand we give assistance and, on the other hand, we develop a model capable to take already known properties of COVID‐19 as well as a later possible passive immunisation by vaccination and a possible loss of immunity of recovered persons into account.

中文翻译：

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建立流行病学模型——开发用于 SARS-CoV-2 传播的 SEI3RSD 模型

本研究调查了建立描述传染病传播模型的基本步骤。结合这些模块，SEI ³将开发 RSD 模型，该模型可以考虑通过疫苗接种可能进行的被动免疫以及不同的潜伏期和潜伏期持续时间。此外，可以区分有无症状的感染者。由于目前用于描述传染病传播的全球 SARS-CoV-2 大流行（COVID-19 大流行）模型及其在预测中的应用已成为科学界和广大公众的关注焦点，超过通常。目前，已经出现了许多关于病毒 SARS-CoV-2 及其引起的 COVID-19 疾病的论文和研究。这发生在医学、病毒学、经济、社会学和其他方面以及数学观点下。关于最后提到的一点，主要重点在于现有模型的应用及其对当前可用感染过程数据的适应。显然，目的是预测可能的进一步发展，例如在德国。调查政治和行政措施（如接触限制、关闭或更确切地说是重新开放学校、餐馆、酒店等）对感染过程的影响尤其重要。这里考虑的用于建立合适模型的步骤长期以来是众所周知的。然而，可以理解的是，它们不会在当前面向应用程序的工作中以扩展的方式处理。因此，本研究的目的是介绍一些现有的建模步骤，而不是为了完整性。因此，我们一方面提供帮助，另一方面，