VaCRO

Purpose

The purpose of VaCRO is to help clinicians minimize open vial waste from multi-dose vials while maximizing immunization coverage. This objective is achieved by determining optimal cut-off times to stop vial reconstitution for a single type of vaccine. Optimal cut-off times are generated for each session (i.e., each clinic work-day) as a function of:

• Total number of vaccination sessions remaining before replenishment (i.e., the next shipment of vaccines)
• Number of vials remaining
• Doses per vial
• Average daily demand (i.e., expected number of patients per session)
• Total number of hours each session

The optimal is generated by a Markov Decision Process model developed by Mofrad et al. (2014). In this framework, the following assumptions are made:

• Vaccines are stored within their manufacturer-recommended ranges at all times
• The shelf life of an open vial is equal to the duration of the session in which it was opened
• All vials have the same vial size

Why Use VaCRO?

To maximize the number of children who receive vaccinations, clinicians must consider efficient ways to operate a vaccination clinic so that they can reduce vaccine waste. The World Health Organization (WHO) estimates that 50% of vaccines are wasted globally, most of which is caused by open vial waste. Open vial waste occurs when a multi-dose vial is reconstituted but its remaining doses are unused before vaccine expiration. One way to reduce open vial waste is to change the vaccine administration policy - the decision rules that dictate when vials are reconstituted. Instead of reconstituting vials whenever patients arrive (regardless of long-term consequences), VaCRO determines optimal cut-off times each sessions for which it is optimal to stop reconstituting vials so remaining inventory is preserved for future demand. The superior performance of this policy is described in Mofrad et al. (2014).