Designing a sustainable vaccine supply chain by considering demand substitution and value-added function during a pandemic outbreak

Abstract

The severe social, economic, and health detriments caused by pandemics (such as COVID-19) lead governments toward exploring survivability challenges. In this regard, some countries produce national vaccines along with receiving global medical supplies, which necessitates the design of a sustainable vaccine supply chain and the evaluation of value-added gained by each vaccine application. Given each vaccine possesses specific efficacy and expiration time, this study addresses products’ brand-based efficacy and perishability derived from existing literature. Additionally, shortages are inevitable in a chaotic pandemic situation as a consequence of limitations in the procurement, distribution, and storage networks of vaccines. Therefore, we investigate the effect of demand substitution based on vaccine efficacy to reduce the unsatisfied demand and combat the prevalence of infection. Moreover, this study implements mobile vaccination centers as well as permanent centers (for instance hospitals and clinics) to relax the personal and geographical constraints of different segments of society and expedite the vaccination. To optimize the multi-objective mathematical model, the augmented ε-constraint method has been utilized, and a real case study is provided to assess the application of the proposed model. The numerical results and sensitivity analysis show the proper utilization of vaccination centers’ combination in our proposed model, also 60% of shortages are compensated by substitutable products, which leads to expeditious immunization.