Improving cold chain technologies through the use of phase change material

Abstract

Vaccine-preventable diseases are responsible for about 25% of the 10 million deaths occurring annually for children under five years of age. The World Health Organization's Expanded Programmes on Immunization succeed in providing standardized guidelines for vaccine storage and distribution, but often fail to accommodate the unique infrastructure between and within countries. In order to better regulate the temperature of vaccines as they travel through countries, we have selected and characterized an appropriate phase change material (PCM) that will resist temperature fluctuations outside of a range of 2-8 °C, based on appropriate thermophysical properties. Additionally, we have integrated the selected PCM within a geometrically and thermally optimized cold box, maintaining long-term stabilization of temperatures within a range of 2-8 °C. In meeting these objectives, we have demonstrated the feasibility of a technological solution that may be readily implemented in the existing vaccine distribution supply chain, or that holds potential to be the centerpiece for new, more efficient vaccine distribution strategies.