Customizing immunization clinic operations to minimize open vial waste

Abstract

Many multi-dose vaccine vials must be used within hours of reconstitution; unused doses are discarded as "open vial waste." Building on Mofrad et al. (2014), we evaluate operating strategies that maximize coverage by controlling open vial waste. We define novel metrics for determining thresholds on vaccination clinic operating hours and session frequency. We study the performance of optimal and heuristic policies in the presence of random vial yield. Cost analyses indicate significant potential savings. Because optimal strategies are context specific, we also develop a decision support tool (available online) to easily replicate the analysis for any problem setting.

Vaccine distribution chains in low- and middle-income countries: A literature review

“…This occurs when a multi-dose vial is opened, but not all doses are administered and mainly depends on the vial size and session size (Assi et al, 2011;Mofrad, Maillart, Norman & Rajgopal, 2014;Mofrad, Garcia, Maillart, Norman & Rajgopal, 2016). Determining whether to provide a vaccine using single-or multi-dose vials is an important decision as this might have various implications for the VDC.…”

“…This results in the need of a thorough trade-off analysis (Heaton et al, 2017). Also, the number of doses per vial in a multi-dose vial can vary (e.g., a 10-dose vial can contain 8, 9 or 10 doses) due to clinician variation, syringe type, and spoilage (Dhamodharan & Proano, 2012;Guichard et al, 2010;Lee et al, 2010;Mofrad et al, 2014;Mofrad et al, 2016;Wallace et al, 2017). Although this is pointed out by numerous papers, only one paper in this literature review (i.e., Mofrad et al, 2016) takes this characteristic into account by introducing random vial yield and vial failures in their model.…”

“…Generally, policy dictates that when a multi-dose vial is depleted, a new vial should be opened upon the arrival of a patient. However, following this administration policy of never turning away a patient results in high OVW rates and frequent stock-outs (Mofrad et al, 2014;Mofrad et al, 2016). Moreover, anecdotal evidence is found of health care workers turning away patients for vaccination when this would result in wasting most of the doses in the vial (Drain et al, 2003;Haidari et al, 2015;Heaton et al, 2017;Lee et al, 2010;Wallace et al, 2017).…”

“…Moreover, anecdotal evidence is found of health care workers turning away patients for vaccination when this would result in wasting most of the doses in the vial (Drain et al, 2003;Haidari et al, 2015;Heaton et al, 2017;Lee et al, 2010;Wallace et al, 2017). Consequently, administration policies are looked into to determine vial opening thresholds above which it is worthwhile to open an additional multi-dose vial (e.g., Haidari et al, 2015;Mofrad et al, 2014;Mofrad et al, 2016;Mofrad, Maillart, Norman & Rajgopal, 2018).…”

“…Correct estimation of OVW is important since it is taken into account when deciding on vaccine ordering quantities and thus can influence the occurrence of stockouts (Chen et al, 2015;Ebong & Levy, 2011;Lim et al, 2017;Rajgopal et al, 2011;Wallace et al, 2017). Hence, reducing waste in the future is imperative as the costs of vaccines and the need for storage capacity are already high and will further increase in the future (Mofrad et al, 2016;Shittu et al, 2016;Songane, 2018). Moreover, the fact that demand already exceeds supply (Erdogan et al, 2017) further underscores the importance of avoiding vaccine wastage.…”