{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T12:42:49Z","timestamp":1774528969185,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,6,27]],"date-time":"2021-06-27T00:00:00Z","timestamp":1624752000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/04106\/2020 (CIDMA); PhD fellowship PD\/BD\/150273\/2019"],"award-info":[{"award-number":["UIDB\/04106\/2020 (CIDMA); PhD fellowship PD\/BD\/150273\/2019"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Axioms"],"abstract":"<jats:p>We propose a qualitative analysis of a recent fractional-order COVID-19 model. We start by showing that the model is mathematically and biologically well posed. Then, we give a proof on the global stability of the disease free equilibrium point. Finally, some numerical simulations are performed to ensure stability and convergence of the disease free equilibrium point.<\/jats:p>","DOI":"10.3390\/axioms10030135","type":"journal-article","created":{"date-parts":[[2021,6,27]],"date-time":"2021-06-27T22:24:57Z","timestamp":1624832697000},"page":"135","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Mathematical Analysis of a Fractional COVID-19 Model Applied to Wuhan, Spain and Portugal"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0119-6178","authenticated-orcid":false,"given":"Fa\u00ef\u00e7al","family":"Nda\u00efrou","sequence":"first","affiliation":[{"name":"Center for Research and Development in Mathematics and Applications (CIDMA), Department of Mathematics, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8641-2505","authenticated-orcid":false,"given":"Delfim F. M.","family":"Torres","sequence":"additional","affiliation":[{"name":"Center for Research and Development in Mathematics and Applications (CIDMA), Department of Mathematics, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"261383","DOI":"10.1155\/2014\/261383","article-title":"On the Mathematical Analysis of Ebola Hemorrhagic Fever: Deathly Infection Disease in West African Countries","volume":"2014","author":"Atangana","year":"2014","journal-title":"BioMed Res. Int."},{"key":"ref_2","first-page":"9352725","article-title":"A Mathematical Model with Quarantine States for the Dynamics of Ebola Virus Disease in Human Populations","volume":"2016","author":"Yanover","year":"2016","journal-title":"Comput. Math. 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