USA: Researchers from the Oak Ridge National Laboratory (ORNL) have collaborated with Carrier to keep Covid-19 vaccines ultra-cool for an extended period in a retrofitted commercial storage container.
Most Covid vaccines are required to be stored at low temperatures, with current transport methods using dry ice to maintain temperatures. However, longer travel times, particularly to remote locations without supportive infrastructure, require extended refrigeration.
The Pfizer vaccine requires storage between -80°C and -60°C, while the Moderna vaccine requires -30°C storage. Pfizer has designed a reusable package for transportation and storage that can keep the vaccine at the target temperature for 10 days. However, the last stage of distribution is quite challenging, especially for rural or suburban areas, where local towns, pharmacy chains and hospitals may not have the infrastructure required to store the vaccine.
Also, the need for a large amount of ultra-low temperature refrigeration equipment in a short time period creates tremendous pressure on the equipment suppliers. In addition, there is limited data available to address ancillary challenges of the distribution framework for both transportation and storage stages. As such, there is a need for a quick, effective, secure, and safe solution to mitigate the challenges faced by vaccine distribution logistics.
In the study, ORNL researchers collaborated with Carrier to create a testbed using a lightweight refrigerated container, vaccine packages and optimal cargo layout and storage rack design that kept temperatures consistent and uniform throughout the container.
The test set out to ensure a significant increase in dry ice life to provide reliable temperature control for vaccine storage. The overall objective of the study assessed the technical merits of utilising container refrigeration units with the ability to control container temperature at -30°C as part of the last mile supply chain for vaccine candidates.
“We significantly increased the dry ice life, providing reliable temperature control and a safe, secure solution for cooling vaccines for transport and last mile storage,” said ORNL’s lead researcher Jian Sun.