American, Delta and United airlines suspend most US- China flights amid coronavirus outbreak

For American Airlines, the nation's largest carrier, the decision comes after the union representing 15,000 pilots sued the company Thursday to immediately halt its US-China service, citing "serious, and in many ways still unknown, health threats posed by the coronavirus."

American moved up its planned suspension of flights between the United States and mainland China beginning Friday. It had originally announced that flights between Los Angeles and Shanghai and Los Angeles and Beijing would be suspended from February 9. Its Hong Kong flights will continue to operate.

"Based on the U.S. Department of State's recent increase of the China Travel Advisory to a Level 4 (Do Not Travel), American is suspending its operations to and from the Chinese mainland beginning today through March 27," it said in a statement.

Delta's said Friday it was suspending all flights from the United States to China from February 6 until April 30. The airline said it's continuing routes until February 5 to "ensure customers looking to exit China have options to do so." It said that it will "continue to monitor the situation closely" and adjust its schedule accordingly.

Affected customers can request a refund, rebook their flight after the suspension lifts or speak with an agent for other options. Delta currently operates 42 weekly flights between the United States and China, including daily service connecting Beijing and Detroit and Seattle, and Shanghai and Atlanta, Detroit, Los Angeles and Seattle.

United Airlines on Thursday extended its suspension of some routes to and from China until March 28. The carrier, which announced its first round of service reductions Tuesday, said it was because of a "significant decline in demand." Flights to Chengdu are not being reduced, it said.

The coronavirus, a potentially fatal respiratory disease, first emerged in Wuhan, China in early December and has since spread across China and appeared in some other countries, including the United States, Japan and India. The World Health Organization has declared the coronavirus epidemic a public health emergency of international concern.

Fears over the spread of the disease has forced both US and global carriers to their schedules as demand for China travel declines.

British Airways, Air Asia, Cathay Pacific, Air India, IndiGo, Lufthansa and Finnair have announced plans this week to slash the number of flights they are operating to China or stop flying to the country entirely. Other airlines are offering customers refunds.