Pandemic Influenza Vaccine Allocation Protocol

This research investigates the impact of alternative allocation mechanisms that can be employed in the context of vaccine inventory rationing. We develop service level expressions for high priority (target groups such as healthcare professionals) and low priority (non-target groups) demand classes using Partitioned Allocation (PA), Standard Nesting (SN), and Theft Nesting (TN) allocation mechanisms. These service level expressions are then utilized to address the two interdependent problems of selecting an appropriate allocation mechanism first and then determining the optimal reserved vaccine quantity accordingly. We conduct numerical experiments on instances with different levels of inventory slackness. From the results of numerical experiments, we observe that there exist certain inventory slackness conditions under which one of the allocation mechanisms outperforms the others. We have evidence that health planners in different regions may exact-order, under-order, or over-order the vaccine inventory with respect to the actual demand for vaccines. Our analysis shows that, depending on the ordering policy devised by the health planners, it is important for the decision maker to choose PA when vaccines are under-ordered and TN when over-ordered. In the case of exact-ordering, if the target groups are in minority TN and when in majority SN is the preferred allocation mechanism.