Extended Covid-19 Models


  • Bernt Lie




COVID-19 models, deterministic models, complex models, vaccination policy


The paper discusses how to extend the SEICUR model with a description of migration. Next, the SEICUR model is extended with a description of age distribution, for the case that infection and serious illness depends on age. Finally, the SEICUR model is extended with models of vaccination. Simulation of the SEICUR model for Italy and Spain indicated that the number of migrants per day between the two countries need to be relatively large before a significant change in infection is noticed. However, this was based on the assumption of average spreaders among the migrants. The age distribution model is mainly of use when considering serious illness and death, and was not pursued further. Vaccination data for Italy, Spain, and Norway, shows that for countries with a low fraction of infected (e.g., Norway), vaccination allows for a noticeable relaxation in mitigation, while for countries which already have a high fraction of infected (e.g., Spain), the effect of vaccination is relatively smaller due to the larger fraction of people already recovered. The extended models allow for a more realistic study of COVID-19 spread, and how to optimize mitigation policies vs. vaccination.


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