This post follows another on in-country Vaccine Transport a week ago, inviting discussion of the post and suggesting we discuss a revision of vaccine transport temperatures around a single temperature requirement; +2C to +8C during 48 hours with excursions <+20C allowed. Based on this assumption we need to look at the cost of alternative transport solutions and, for the passive containers, the packing efficiency of containers in the vehicle. We need to know the cost and efficiency of the options and the optimal choice of routing when selecting the best solution. The table below lists five alternatives taken from the Senegal study within the project ‘Optimize’. Containers 1 and 2 will compete with the current cold boxes, having a larger vaccine capacity and a much better packing efficiency. But these containers are not yet commercialized.
Total container and transport cost per litre routine vaccines delivered by route plan
Four issues emerge from these results and they should be discussed in the context of vaccine supply systems:
* Overall, the refrigerated vehicle is both the least cost per litre of vaccine transported and provides the greatest flexibility to distribute vaccine in secondary or tertiary packing. However, availability of appropriate maintenance services is critical to operate active refrigeration where the road system is rough.
* The influence of route planning to maximise efficiency of distribution and to minimize the cost is evident and may be the critical factor in planning vaccine supply systems
* The larger vaccine capacity and higher efficiency of the two new containers increases the amount of vaccine that can be carried in a given truck but:
- The new containers will not be commercialised unless country programs declare an interest in buying them;
- Their weight (>100kgs) requires rolling and lifting trolleys which, in turn require smooth floor finishes and preferably no changes in level;
- Large or palletized air-shipment materials may be hard to handle, store and dispose if re-used at sub-national levels.
* Re-use of air-shipment palletized containers is usually associated with storing vaccines on arrival at the central store in their tertiary packing materials. This option is several times more bulky to store than unpacking the vaccine, but is often chosen by countries for ease of handling during reception and despatch.
In the scenarios that were studied in Senegal, the highest-cost option was the Dometic RCW25, the traditional vaccine cold box, due to its small capacity relative to the other potential container options and in most situations, its needless extra cold life performance. Furthermore, the model tested was not ‘freeze-free’ and it is probable that as this type of box reaches the market in freeze-free format the capacity for vaccine will be driven down even further.
John Lloyd
8th December 2014