At first sight, they look like regular containers. But the rectangular boxes made by German company Va-Q-Tec will in fact play a key role in keeping life-saving Covid-19 vaccines ultra-cool as they are shipped across the world, reports AFP.

There will be an enormous logistical challenge to transport billions of vaccine doses at the right temperature across the globe, maintaining the so-called “cold chain” from a vaccine manufacturer into a patient's arm. Pfizer/BioNTech's vaccine for instance, must be stored at a frigid minus 70 degrees Celsius.

The Va-Q-Tec containers will serve this purpose of keeping the vaccines cool enough, the company's founder and chief executive Joachim Kuhn told AFP, describing them as “big thermos flasks”.