The equivalent of 8000 Boeing 747s will be needed for shipping a coronavirus vaccine around the world, the International Air Transport Association (IATA) has said.
"Safely delivering COVID-19 vaccines for all 7.8 billion people on the planet will be the mission of the century for the global air cargo industry. But it won't happen without careful advance planning. And the time for that is now," said IATA's chief executive Alexandre de Juniac.
There is no COVID-19 vaccine yet, but IATA is already working with airlines, airports, global health bodies and drug firms on a global airlift plan.
The distribution programme assumes only one dose per person is needed.
About 140 vaccines are in early development, and around two dozen are now being tested on people in clinical trials.
IATA's statement on the aviation industry's challenges in shipping worldwide the vaccine come as one significant trial of a leading candidate faced a serious setback. AstraZeneca on Tuesday said it has paused global trials, including large late-stage trials, of its experimental coronavirus vaccine developed with the University of Oxford because of an unexplained illness in a study participant.
While airlines have been shifting their focus on delivering cargo during the severe downturn in passenger flights, shipping vaccines is far more complex.
Not all planes are suitable for delivering vaccines as they need a typical temperature range of between 2 and 8 degree Celcius for transporting drugs. Some vaccines may require frozen temperatures which would exclude more aircraft.
"We know the procedures well. What we need to do is scale them up to the magnitude that will be required," added Glyn Hughes, the industry body's head of cargo.
Flights to certain parts of the world, including some areas of South East Asia, will be critical as they lack vaccine-production capabilities, he added.
Distributing a vaccine across Africa would be "impossible" right now IATA says given the lack of cargo capacity, size of the region and the complexities of border crossings.
Transportation will need "almost military precision" and will require cool facilities across a network of locations where the vaccine will be stored.
IATA has urged governments to begin careful planning now to ensure they are fully prepared once vaccines are approved and available for distribution.
Along with making sure they are handled and transported at controlled temperatures, security is another issue.
"Vaccines will be highly valuable commodities. Arrangements must be in place to keep ensuring that shipments remain secure from tampering and theft," added IATA.