The Uncertain Times of COVID Mass Vaccine Deliveries: from Start-up to Steady-State

Mass vaccination campaigns have been adopted throughout the world as a major tool to stop the spread of COVID or at least abate its lethal consequences. Smart vaccination strategies have been proposed to make the most efficient use of the scarce resources (e.g., medical and nursing staff) and achieve vaccination aims (i.e., vaccinating as many people as possible in the shortest possible time). However, smart strategies may fail if vaccine deliveries are erratic or do not exhibit even statistical regularity. In this paper, we perform a statistical analysis of up-to-date vaccine delivery data to uncover regularities and use them to draw a probabilistic model of vaccine deliveries that may help optimize and evaluate smart vaccination strategies. We find that for two out of three vaccine manufacturing companies, deliveries concentrate on one or at most two days over a week, though the actual day may be modelled by an arithmetic distribution. © 2022 IEEE.

Planning a Mass Vaccination Campaign with Balanced Staff Engagement

The insurgence of the COVID pandemic calls for mass vaccination campaigns worldwide. Pharmaceutical companies struggle to ramp up their production to meet the demand for vaccines but cannot always guarantee a perfectly regular delivery schedule. On the other hand, governments must devise plans to have most of their population vaccinated in the shortest possible time and have the vaccine booster administered after a precise time interval. The combination of delivery uncertainties and those time requirements may make such planning difficult. In this paper, we propose several heuristic strategies to meet those requirements in the face of delivery uncertainties. The outcome of those strategies is a daily vaccination plan that suggests how many initial doses and boosters can be administered each day. We compare the results with the optimal plan obtained through linear programming, which however assumes that we know in advance the whole delivery schedule. As for performance metrics, we consider both the vaccination time (which has to be as low as possible) and the balance between vaccination capacities over time (which has to be as uniform as possible). The strategies achieving the best trade-off between those competing requirements turn out to be the q-days ahead strategies, which put aside doses to guarantee that we do not run out of stock on just the next q days. Increasing the look-ahead period, i.e. q, allows to achieve a lower number of out-of-stock days, though worsening the other performance indicators. © 2022, Springer Nature Switzerland AG.

Mass Vaccine Administration under Supply Uncertainty

The insurgence of COVID-19 requires fast mass vaccination, hampered by scarce availability and uncertain supply of vaccine doses and a tight schedule for boosters. In this paper, we analyze planning strategies for the vaccination campaign to vaccinate as many people as possible while meeting the booster schedule. We compare a conservative strategy and q-days-ahead strategies against the clairvoyant strategy. The conservative strategy achieves the best trade-off between utilization and compliance with the booster schedule. Q-days-ahead strategies with q < 7 provide a larger utilization but run out of stock in over 30% of days. © 2021 Polish Information Processing Society.