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Collocation method with flood-based metaheuristic optimizer for optimal control ...
            have their ways of spreading and hiding from      handling large-scale, nonlinear systems or multi-
            immune systems, showed how hard it is to con-     objective problems. In addition, there are still
            trol epidemics with more than one strain. These   significant gaps in the research about improv-
            changes are affected by competitive exclusion, in  ing control strategies for multi-strain vaccination
            which one strain beats out others, and coexis-    programs.   Specifically, many studies have not
            tence, in which different strains can stay alive  fully explored the role of strain amplification in
            due to reinfection, cross-immunity, and muta-     disease transmission, leaving this aspect largely
            tion. The optimal control theory allows us to plan  underexplored. Also, even though it is important
            strategies, like immunizations, isolation, and pub-  to find the best ways to control diseases, not many
            lic awareness campaigns, that stop the spread of  studies have looked at how to use computers to
            disease as much as possible while considering the  quickly solve these kinds of problems (called op-
            cost and availability of healthcare.              timal control problems, or OCPs) for multiple
                                                              strains of diseases. This study addresses these
                Multi-strain epidemic mathematical models
                                                              challenges by proposing a hybrid framework inte-
            build on single-strain frameworks like SIR and
                                                              grating a Laguerre-based collocation method with
            SEIR by adding compartments and parameters
                                                              the flood-based metaheuristic optimizer (FBMO).
            to account for how strains interact, how trans-
                                                              This method improves computation speed, deals
            mission and recovery rates change, and how in-
                                                              with the complexity of multi-strain dynamics,
            terventions affect different groups. These mod-
                                                              and looks into areas that have not been explored
            els enable researchers to quantify the impact of
                                                              much, like strain amplification and the best way
            control strategies and predict their outcomes un-
                                                              to vaccinate. By applying the proposed frame-
            der different scenarios. Using optimal control on  work to real-world COVID-19 data from Morocco,
            these kinds of models lets us find the levels of in-
            tervention (like vaccination rates or policies that  we demonstrate its robustness and practical rele-
            keep people from interacting with each other)     vance for managing multi-strain epidemics effec-
                                                              tively. Therefore, the study adds to the knowl-
            that minimize objective functions like the disease
                                                              edge about optimal control theory for epidemic
            burden and the costs of intervention. Key ar-
                                                              models by looking into previously unexplored as-
            eas of focus in these models include finding the
                                                              pects of strain amplification and improving vac-
            best way to vaccinate so that limited resources
                                                              cination strategies. Another key objective is to
            are used efficiently, finding the right balance be-
                                                              provide a computationally efficient approach for
            tween isolation measures to stop the spread of
                                                              solving the OCP, which can enhance the precision
            disease without causing too many social and eco-
                                                              and effectiveness of control measures in managing
            nomic problems, and raising awareness about self-
                                                              the pandemic. The innovation also lies in utiliz-
            protection to get more people to follow through   ing Laguerre polynomials to transform the OCP
            and lower the risk of getting sick. 4–6
                                                              into an NLP, making it computationally efficient
                To better understand how COVID-19 and         and providing better ways to handle multi-strain
            its multi-strain variants move and behave, many   pandemics like COVID-19.
            mathematical models have been created to show         The proposed methodology offers several key
            how the epidemic spreads (see Table 1). We have   benefits. The study ensures that the system’s dy-
            employed these models to investigate the dynam-   namics are accurately represented using the col-
            ics of the pandemic and explore control measures,  location method, making solving the OCP easier.
            such as vaccination strategies, to mitigate its   Adding the FBMO improves the global optimiza-
            spread. Further research is still needed, though,  tion, making it possible for the NLP to be solved
            especially on the best ways to keep COVID-19      quickly. The practical application of this frame-
            under control in vaccination programs, especially  work to real-world COVID-19 data from Morocco
            when it comes to multi-strain variants.    This   highlights its relevance and utility in optimiz-
            study addresses this knowledge gap by compre-     ing vaccination, isolation, and public awareness
            hensively reviewing the current literature on opti-  strategies. Therefore, this study helps move the
            mal control strategies for COVID-19 multi-strain  field forward by examining multi-strain epidemic
            vaccination.                                      control’s theoretical and practical sides and pro-
              Even though there have been improvements,       vides a valuable tool to address complex public
            many studies that look at multi-strain epidemic   health issues on a large scale.
            control still use old-fashioned methods like the      This paper’s orthogonal Laguerre collocation
            Pontryagin Maximum Principle and Runge-Kutta      method presents numerous benefits, including
            methods.    While effective in specific contexts,  augmenting computational effectiveness, guaran-
            these approaches often encounter difficulties in  teeing precise solutions, improving efficiency and
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