Vaz, SandraTorres, Delfim F. M.2022-11-212022-11-212021-11-23Vaz, S.; Torres, D.F.M. A Discrete-Time Compartmental Epidemiological Model for COVID-19 with a Case Study for Portugal. Axioms 2021, 10, 314. https:// doi.org/10.3390/axioms10040314http://hdl.handle.net/10400.6/12424Recently, a continuous-time compartmental mathematical model for the spread of the Coronavirus disease 2019 (COVID-19) was presented with Portugal as case study, from 2 March to 4 May 2020, and the local stability of the Disease Free Equilibrium (DFE) was analysed. Here, we propose an analogous discrete-time model and, using a suitable Lyapunov function, we prove the global stability of the DFE point. Using COVID-19 real data, we show, through numerical simulations, the consistence of the obtained theoretical results.engMathematical modellingEpidemiologyCOVID-19 pandemicQualitative theoryLyapunov functionsNumerical simulations with real datajournal article10.3390/axioms10040314