Research On Responsive Influenza Vaccine Supply Chain Under Time-sensitivity Demand

Influenza is a seasonal epidemic that spreads quickly and is highly contagious and pathogenic.According to the World Health Organization,the global pandemic causes approximately 3 million to 5 million serious cases each year,and about 290,000 to 650,000 deaths related to respiratory diseases.Influenza causes serious illness and death worldwide,and it brings huge economic losses to human society.Influenza vaccination is the most effective way to prevent influenza.Vaccination before the outbreak of the flu season can effectively control the spread of the flu,significantly reduce the hospitalization rate and the cause of death caused by the flu,saving medical cost.Due to the seasonality,high yield uncertainty,and high distribution requirements,there is a risk that influenza vaccines will not be marketed in time during the peak period(ideal period)of influenza vaccination.The demand for influenza vaccines is time-sensitive,because some unserved customers will not return for vaccination after the ideal period.Failure to market the flu vaccine in time will result in the loss of demand.This paper studies a supply chain system consisting of a manufacturer and a responsive pricing retailer,and discusses the management problem of a time-sensitive demand influenza vaccine supply chain.Firstly,this paper studies the optimal ordering and pricing strategies of the centralized supply chain.It is found that with the increase of the order quantity,the expected sales quantity increases,and remains unchanged when the order quantity increases to a certain extent.And with the increase of the unit retail price,the expected sales is first maintained at a higher level and then begins to decrease to zero.Both the centralized supply chain and the decentralized supply chain's profits are declining as the unit production cost increases.When the unit production cost of the influenza vaccine is small,the loss caused by shortage is greater than the unsalable cost of the product.Therefore,in order to avoid the shortage of influence vaccine,the supply chain adopts an adventurous ordering strategy and orders to fulfill the ideal period demand.On the contrary,when the unit production cost is high,compared with the shortage cost,the loss of the supply chain caused by unsold products is greater.Therefore,in order to avoid unsalable vaccine,the supply chain adopts a prudent ordering strategy and orders to fulfill the late period demand.However,a decentralized supply chain will change the ordering strategy at a smaller unit production cost,which will result in the loss of the total profit of the supply chain.Then this paper studies the coordinating effect of several commonly used supply chain coordination contracts.It is found that linear discount contracts,such as buyback contract,rebate contract and quantity discount contract,cannot coordinate the supply chain,and perform even worse than the decentralized supply chain.However,using the revenue sharing contract can coordinate the supply chain,maximizing the total profit.The manufacturer provides the influenza vaccine to the retailer at a unit wholesale price lower than the unit production cost,and then obtain a certain proportion of the total sales revenue.The increase in total profit in the supply chain can be flexibly distributed among members of the supply chain by the bargaining power of the manufacturer.Furthermore,because influenza vaccination is an important public health service,affecting people's health and living standards,this paper studies the relationship between influenza vaccine supply chain and social welfare.We found that with the increase of unit production cost of influenza vaccine,the optimal social welfare gradually decreases to zero.It means that when the unit production cost is high,the cost of influenza vaccination is less than the economic loss of per capita infection,so we need to encourage as many as individuals to vaccinate.We should encourage the supply chain to increase the order quantity and reduce the unit retail price.Conversely,when unit production costs are high,people need to be prevented from vaccinating.By subsidizing or taxing from the retailer,the decentralized supply chain can maximize social welfare.