1. School of Statistics and Mathematics, Shanghai Lixin University of Accounting and Finance, Shanghai 201620, China
2. College of Finance, Lancaster University, Lancaster LA2 0PF, UK
| Abstract: | Since the discovery of COVID-19 at the end of 2019, COVID-19 has begun to circulate in various countries around the world, and the virus strains are constantly mutating. The policy of "dynamic zero clearing" implemented in China has achieved good epidemic prevention effect. In the spring and summer of 2021, the local recurrent strains in Chinese Mainland and the imported variants Delta strain and Delta+ strains formed another wave of epidemic. Objective: In order to further study the changes of important parameters such as the basic reproduction number and infection rate of mixed strains, the number risk of confirmed cases and asymptomatic cases in the future was predicted according to the SAIR mathematical model. The effects of various epidemic prevention measures are discussed. Methods: Formula calculation and data fitting were used. Results: The values of important parameters were calculated again, and the effect data of epidemic prevention measures were discussed. Conclusion: The number of confirmed cases, the number of asymptomatic infections, and the development of the number of cases simulated by our SAIR model are in good agreement with the actual data. The new infection parameters and other data show that the infectivity of the new mixed strains is much stronger than that of the original strains in the past. In particular, the number of asymptomatic infections has increased significantly. We need to draw everyone's attention. The simulation shows that all strict epidemic prevention measures are effective, and strict epidemic prevention should be adhered to. |
| Keywords: | COVID-19; SAIR Model; Delta Strain; Confirmed Case; Asymptomatic Case |
| DOI: | 10.57237/j.mrf.2022.01.005 |
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