Two weeks ago, at the Technet 2023 conference in Panama, there was much discussion on vaccine wastage, especially unavoidable opened vial wastage. It is a very hot topic, but it need not be so hot.
In 2020, WHO published an article in Vaccine on vaccine wastage in routine vaccination sessions (attached).
I implore you to read the article. The findings and recommendations were endorsed by WHO’s Immunization Practices Advisory Committee (IPAC).
The new knowledge within the article (that routine session sizes are governed by Binomial statistics) allows you to calculate the expected wastage rates for each health facility, district or country, based only on its target population and session frequencies. This information can be used to better plan immunization service delivery (to reduce wastage & increase coverage), to forecast vaccine needs, to optimize vial sizes, and to monitor vaccine wastage.
WHO is developing 2 apps based on the findings to facilitate 2 of these tasks: session planning and forecasting. These tools will hopefully be rolled out early next year. Watch this space!
The article is a bit wordy and technical, so I have also attached a more digestible presentation of the analysis. And I have also attached a wee toy that you can play with to help you understand Binomial statistics, session sizes, wastage rates, and safety stocks.
It is high time this new knowledge is common knowledge, and used in countries, to better plan vaccination sessions, better forecast vaccine needs, and better monitor vaccine wastage. So, please review the content, digest it, and do not hesitate to contact me if you have any questions or suggestions.
All the best, Paul
P.S. I have also studied and modelled wastage rates in campaign settings (nOPV2 campaigns) and in appointment-based systems (UK’s Covid campaign). I cannot share the findings of the former just yet, but for the latter, I do have a model and guidance for appointment-based campaigns, which I’d be happy to share and discuss if you are interested.