This article presents, within a multiscale framework, a search for a unified approach towards modelling the COVID-19 pandemic, from contagion to within-host dynamics. The modelling is focused on vaccination and therapeutical actions in general. The first part of our article is devoted to understanding the complex features of the system and to the design of a modelling rationale. Then, the modelling approach follows mainly focused on the competition between the proliferating virus and the immune system. Modelling considers also the action of vaccination plans related to the onset of new variants. This article is part of the theme issue 'Kinetic exchange models of societies and economies'.
Pandemics of mutating virus and society: a multi-scale active particles approach