The quickly spreading coronavirus outbreak in China is set to begin impacting air travel to Asia as United Airlines just announced it is suspending 48 flights between the U.S. and China.

Beginning on February 1, 16 flights between SFO and China are temporarily going off the books, and for now they are set to resume on February 9, though that may change. These include four flights between SFO and Hong Kong — two westbound and two eastbound — and 12 flights between SFO and Shanghai. United said in a statement that the suspensions are due to "load factors," i.e. not enough bookings on the flights, and not due to virus fears. The airline will continue to operate thrice-weekly flights to Beijing, Shanghai, and Chengdu from SFO.

Other flights to China are being halted out of Newark, Chicago O'Hare, and Washington Dulles airports. As the SF Business Times notes, United is offering to provide full refunds to passengers who had tickets booked on any of the canceled flights.

United is the first airline to cancel any flights to or from China amid the virus crisis, but more may be yet to come. Also, large American companies are beginning to institute travel bans for their employees, with Facebook and Ford among the big companies telling workers they can't go to China for now.

Meanwhile, as has been making the rounds on local social media, a China Southern Airlines flight from Wuhan landed at SFO at 10:08 a.m. this morning. (Not sure if that's a frequent flight, or what.)

The company said that the decision was made "due to a significant decline in demand for travel to China," and they added, "We will continue to monitor the situation as it develops and will adjust our schedule as needed."

The Wuhan coronavirus has reportedly infected 4,515 people, with around 2,700 of those confirmed cases in the central Chinese province of Hubei, where Wuhan is located and where the outbreak first began. The death toll reached 106 as of Tuesday, exceeding the 100 mark for the first time. No deaths have yet to occur outside of China, and five cases have been confirmed thus far in the U.S.

As the New York Times reports, the United States is now screening passengers arriving from central China at 20 different airports. And today, a charter flight carrying State Department personnel and other U.S. citizens was arriving here from Wuhan, routing through Anchorage and landing in Ontario, California. Officials said that everyone on board would be screened for symptoms three times between takeoff and their arrival in Alaska.

Related: Patients Tested For Deadly Coronavirus In East Bay