The group's financial estimate is based, however, on the disruption caused by SARS when it ripped through China in 2003. That virus caused real damage over a period of months, including for airlines, but the sharp decline in activity was "followed by an equally quick recovery," according to IATA.

"We don't yet know exactly how the [current] outbreak will develop and whether it will follow the same profile as SARS or not," the group warned.

Maersk, the world's largest container shipping company, said Thursday that it was having a "very weak" start to the year, with factories in China, which make the goods it transports, running at around 50% to 60% of capacity. CEO Søren Skou said he expects production to ramp up to 90% by the first week of March, but he cautioned that there are "still a lot of uncertainties."