Here's a good explainer from Reuters on the airline industry's response to the Wuhan coronavirus outbreak so far. If the virus spreads becomes a pandemic, this could impact world financial markets as did SARS in 2003.
SARS killed about 800 people. Since then, people travel by plane even more, and other things have changed in global travel patterns.
"The biggest concern is a sharp drop in travel demand if the virus becomes a pandemic."
Many airlines, including Korean Air Lines, Singapore Airlines' budget carrier Scoot, Taiwan's China Airlines Ltd and Japan's ANA, announced they were cancelling flights in and out of Wuhan after authorities announced a lockdown.
South Korean budget carrier T'way Air earlier this week postponed the scheduled launch of a new route to the city.
Flight tracking website FlightRadar24 showed that as of 0600 GMT on Thursday, 184 Wuhan flights, or 60% of the departures listed for the day, had been canceled.
Wuhan's Tianhe airport serves around 2% of China's total air traffic and mainly serves domestic routes. Broker Jefferies estimated 88.8% of overall flights are domestic, with China Southern Airlines Co Ltd holding the largest market share at 30%.