FRANKFURT : Getting a coronavirus vaccine from manufacturing sites to some parts of the world with rural populations and unreliable electricity supply will be an immense challenge, given the need to store some vials at temperatures as low as minus 80 degrees Celsius (-112 Fahrenheit), Deutsche Post warned on Tuesday.The German logistics firm said that distribution of an eventual vaccine across large parts of Africa, South America and Asia would require extraordinary measures to keep deliveries of so-called mRNA vaccines refrigerated at Antarctic-level temperatures.Companies developing vaccines requiring exceptional cold storage, such as Moderna and CureVac, are working hard to make their injections last longer in transit.The novel class of.