Cold chain time-and temperature-controlled transport of vaccines: A simulated experimental study

Purpose: The objective of this research was to examine the cold chain temperature maintenance for the supply of vaccines and other biological products by pharmaceutical wholesaler. Materials and Methods: In this study, six configurations using cold vaccine boxes or bags made with different materials, with and without insulation, of different sizes, and number of coolant-packs were used to simulate the configuration used by the pharmaceutical wholesal-ers for transportation of vaccine. Model vaccines (vial, n=10) were packed using these six configurations which then stored in an incubator at 38ºC and monitored for 24 hours. Each configuration was tested repeatedly for 5 times. Results: In term of compliance to 2°C–8°C, four out of six tested configurations are effective in cold chain transportation. The effectiveness is highly dependent on the type of passive con-tainers used, size of cold boxes, insulation, and number of coolant-packs. The configuration with a larger polystyrene foam box with five coolant-packs maintained the required temperature up to 23 hours. In contrast, configurations using a polystyrene foam box with four coolant-packs and a large vaccine cold box with two coolant-packs failed to reach below 8ºC through-out the 24 hours. Conclusion: Packaging method, the material and size of the container could have a direct impact on the effectiveness of cold chain temperature maintenance. Polystyrene foam box, cold box with polyethylene interior lining and polypropylene insulation, a cooler bag with proper number of ice packs could be effectively used for transportation of vaccines within their res-pective transportation duration allowance.