How many doses should go in a vaccine vial?

by Cecily Stokes-Prindle and Lois Privor-Dumm, IVAC It sounds like a pretty mundane question, but the answer has major implications for delivering vaccines in low- and middle-income countries. Having consulted with experts from across the world, researchers at the International Vaccine Access Center (IVAC) are putting together a framework document to help decision-makers find the right answer. A single decision on the size and type of a vaccine container can have significant implications for that vaccine’s safety, affordability, and coverage. Choosing a single-dose vial instead of a multi-dose vial or a prefilled syringe, for example, affects a wide variety of stakeholders: the manufacturers who make vaccines, the governments and organizations that buy them, the health workers who administer the vaccines, and the patients who benefit from their protection. In lower-income countries, common Expanded Programme on Immunization vaccines (such as bacillus Calmette-Guérin, measles, diphtheria-tetanus-pertussis, and polio) have traditionally been packaged in vials containing up to 20 doses. These multi-dose vials are easy to package, store, and transport and are, therefore, less costly than single-dose vials. However, with multi-dose vials there is an increased chance that unused doses will go to waste. A recent IVAC study found that wastage rates among 19 GAVI Alliance-eligible, low-income countries ranged from 4 to 44 percent for 10-dose containers, compared to just 1 to 10 percent for single-dose vials. How does this wastage occur? Once a vial is opened, health providers only have a set amount of time to administer all of the doses—for some vaccines, just a matter of hours—before they must be thrown away. With traditional vaccines, the cost of a wasted dose is negligible compared to the cost of purchasing and transporting vaccines in single-use vials. Doses of measles or polio vaccine, for example, can cost less than $0.20 each. As countries introduce newer and more expensive vaccines, however, the cost equation is changing. For example, by 2015, the GAVI Alliance forecasts that up to 58 of the world’s poorest countries will be using pneumococcal conjugate vaccines at a price to the countries of up to $3.50 per dose. At this price, wastage becomes a more significant driver of costs and, therefore, a greater concern. This concern is prompting stakeholders to examine the programmatic and cost impact of smaller vial sizes. Previous analyses of container choice have focused on cost and volume considerations without fully analyzing the impact of this choice on safety, demand, and overall immunization coverage. A tool for systematic, transparent analysis of the factors and trade-offs involved could improve vaccine container decisions, ultimately improving overall vaccine coverage and reducing preventable illness and death. Different scenarios will likely require different solutions, but identifying the crucial issues and relationships can help establish a framework for decision-making. To that end, health experts from around the world recently convened in Washington, DC, to review the evidence and develop a framework to define the most appropriate dimensions for vaccine primary containers. Leaders from developing countries, WHO, UNICEF, vaccine manufacturers, academia, and nongovernmental organizations shared available evidence, presented new research, and gave feedback on the draft framework. The framework is now being finalized and will be published later this year. The primary container framework identifies three key priorities that influence decision-making: coverage, affordability, and safety. -Coverage is simply about vaccinating as many children as possible. Overall supply, availability of transportation and storage, and consumer demand levels can all affect coverage, and each of those things can be directly or indirectly affected by container choice. -Affordability is about keeping the cost of vaccines and vaccine delivery systems within reach for countries and families—but it is also about improving communication and building partnerships so that pharmaceutical companies can provide products at a reasonable price. -Safety is about making packaging choices that reduce the likelihood of needle reuse, vial contamination, or injection of expired vaccine. Most of all, it is about ensuring that the average health worker will have the capacity and tools to deliver a safe, timely injection to every child. These three priorities interact with each other—and with the larger global health context—to affect the ultimate outcome we all strive for: healthy children and families. It is clear that answering the question of how many doses should go in a vial involves much more than cost and the size or number of freezers and cold packs needed. Vaccine safety, waste disposal, delivery issues and supply availability are all potentially impacted by this unglamorous decision. It may seem mundane on the surface, but the answer to this question could potentially have huge implications on how many millions of children we vaccinate, how safely we vaccinate them, and how much money we save (or waste) in the process. For more information on the primary container framework, please visit the IVAC website or contact [[email protected]]Cecily Stokes-Prindle[/email]. To comment, make sure you are logged in and click Reply.