(CNN)As vaccines start to be administered across the world, the beginning of the end of the pandemic is at last in sight.
But some countries are at risk of missing out. While the African Union has secured 270 million vaccine doses for distribution across the continent, in addition to those promised by the global vaccine program COVAX, this could still fall short of demand for the region.
Even if enough vaccines are secured, there is an enormous logistical challenge: how to transport temperature-sensitive vaccines to places without reliable electricity and refrigeration.
The answer is in developing a "cold chain" -- a network of vehicles, fridges and cold rooms -- that can be used to transport the vaccine seamlessly from the manufacturer to the immunization point.