Vaccine pricing and production capacity in Africa: can Africa move beyond pooled procurement in the face of a future pandemic?

We examine Africa's vaccine manufacturing potential,spurred by the coronavirus disease 2019(COVID-19)pan-demic,while critically analyzing vaccine price inequities and procurement strategies during the pandemic,with anticipation of future outbreaks.Although Africa consumes approximately 25%of the global vaccine supply,over 99%of these vaccines are produced outside the continent,primarily due to insufficient local investment.Vaccine procurement strategies have relied heavily on pooled procurement mechanisms and tiered-pricing mod-els,predominantly controlled by external organizations.Significant disparities in vaccine pricing have resulted in vaccine price inequities,with evidence suggesting price discrimination,where different prices are charged for the same vaccine across countries and regions.While vaccine prices are only one component of vaccination cam-paign costs,the inequitable pricing of vaccines poses serious challenges to fair access,especially in low-income countries.Given the inevitability of future pandemics and other outbreaks,the central question remains:Does Africa possess the capacity to strengthen its vaccine production infrastructure and reduce dependency on ex-ternal suppliers?Our review reveals that,with robust political commitment,enhanced investment in Research and Development,and leveraging the heterogeneous nature of the regional bloc,Africa has made strides toward establishing vaccine manufacturing hubs with the potential for substantial capacity expansion.Furthermore,we argue for a regional campaign based on the principles of the fair priority model as an ethical framework for vaccine procurement,which prioritizes need and ensures equitable distribution,thereby complementing existing pooled procurement arrangements in times of future pandemics.This paper concludes with two key recommen-dations based on lessons learned from the COvID-19 crisis and future preparedness.First,Africa must push for a transparent and equitable tiered-pricing structure to ensure affordability for all Second,intentional and sustained investment in R&D is critical to addressing systemic inequities in vaccine supply,not only for cOVID-19 but for future outbreaks and routine immunization programs.

Study on the Problem of Multistage Vaccine Production and Allocation with Capacity Constraints

Vaccination is the best way to build an immune barrier to control a new infectious disease.Considering the limited production capacity at the initial stage of vaccine production,the problem of multistage vaccine production and allocation is studied under the policy of free treatment for infected patients by the government.Given the population and infection rates of different regions and the vaccine production capacity of each stage,an integer programming model is established to minimize the sum of production-and-vaccination cost and treatment cost of infected patients,which is solved by the GUROBI solver.The correctness of the model is verified by simulation,and the necessity of considering the treatment cost of infected patients in the objective function is further analyzed,which confirmed the correctness of the free treatment policy for patients in China.A heuristic algorithm is designed to solve the large-scale problem and numerical experiments are conducted to verify the efficiency of this algorithm.Furthermore,based on the sensitivity analysis results of parameters,the optimal vaccine production and allocation strategy are proposed,which provide the decision basis for the government departments to make reasonable vaccine production and vaccination plan.

A Deleted Deletion Site in a New Vector Strain and Exceptional Genomic Stability of Plaque-Purified Modified Vaccinia Ankara(MVA)

Vectored vaccines based on highly attenuated modified vaccinia Ankara(MVA) are reported to be immunogenic, tolerant to pre-existing immunity, and able to accommodate and stably maintain very large transgenes. MVA is usually produced on primary chicken embryo fibroblasts, but production processes based on continuous cell lines emerge as increasingly robust and cost-effective alternatives. An isolate of a hitherto undescribed genotype was recovered by passage of a nonplaque-purified preparation of MVA in a continuous anatine suspension cell line(CR.pIX) in chemically defined medium.The novel isolate(MVA-CR19) replicated to higher infectious titers in the extracellular volume of suspension cultures and induced fewer syncytia in adherent cultures. We now extend previous studies with the investigation of the point mutations in structural genes of MVA-CR19 and describe an additional point mutation in a regulatory gene. We furthermore map and discuss an extensive rearrangement of the left telomer of MVA-CR19 that appears to have occurred by duplication of the right telomer. This event caused deletions and duplications of genes that may modulate immunologic properties of MVACR19 as a vaccine vector. Our characterizations also highlight the exceptional genetic stability of plaque-purified MVA:although the phenotype of MVA-CR19 appears to be advantageous for replication, we found that all genetic markers that differentiate wildtype and MVA-CR19 are stably maintained in passages of recombinant viruses based on either wildtype or MVA-CR.