Modeling and optimal control of mutated COVID-19 (Delta strain) with imperfect vaccination

Abstract

As people around the world work to stop the COVID-19 pandemic, mutated COVID-19 (Delta strain) that are more contagious are emerging in many places. How to develop effective and reasonable plans to prevent the spread of mutated COVID-19 is an important issue. In order to simulate the transmission of mutated COVID-19 (Delta strain) in China with a certain proportion of vaccination, we selected the epidemic situation in Jiangsu Province as a case study. To solve this problem, we develop a novel epidemic model with a vaccinated population. The basic properties of the model is analyzed, and the expression of the basic reproduction number is obtained. We collect data on the Delta strain epidemic in Jiangsu Province, China from July 20 to August 5, 2021. The weighted nonlinear least square estimation method is used to fit the daily asymptomatic infected people, common infected people and severe infected people. The estimated parameter values are obtained, the approximate values of the basic reproduction number are calculated . Through the global sensitivity analysis, we identify some parameters that have a greater impact on the prevalence of the disease. Finally, according to the evaluation results of parameter influence, we consider three control measures (vaccination, isolation and nucleic acid testing) to control the spread of the disease. The results of the study found that the optimal control measure is to dynamically adjust the three control measures to achieve the lowest number of infections at the lowest cost. The research in this paper can not only enrich theoretical research on the transmission of COVID-19, but also provide reliable control suggestions for countries and regions experiencing mutated COVID-19 epidemics.

Optimal control and cost-effectiveness analysis of a new COVID-19 model for Omicron strain

“…For more introduction and application of the algorithm, please refer to Ref. [44] , [45] , [46] , [47] . In order to explore the control effect of control measures, we designed the following control scenarios, namely single, coupled and threefold control strategies.…”

Analyzing the Effect of Social Distancing Policies on Traffic at Sinchon Station, South Korea, during the COVID-19 Pandemic in 2020 and 2021

“…10.5 26.7 -Some incentives that ease restrictions for vaccinated people provided (1 July 2021) 3) Jul. 4) Aug. 4) Sep. During the occurrence of large-scale local community transmission related to religious groups, the health authorities raised the public alert level, which comprises four tiers, to the highest level of "serious" on 23 February 2020, and social distancing was first introduced for COVID-19 on 29 February 2020 [14,45,46]. In the following month (March), although Seoul had a relatively small number of new positive cases, the SMG preemptively launched a campaign with "Hold up!…”

“…The rapid spread of cases around the world led to COVID-19 being declared a global pandemic by the World Health Organization (WHO) in March 2020 [ 1 , 2 ]. Because of the emergence of new coronavirus variants in many places and their strong infectivity, the COVID-19 pandemic is recognized as one of the most serious global health problems [ 3 , 4 ]. Therefore, most countries implemented lockdown measures, applying various restrictions such as closing their borders, reducing business activity, delaying school opening times, and restricting traffic [ 5 ].…”

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A Mathematical Model for a Transmissible Disease with a Variant

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