Dow tumbles on the first case of coronavirus in the United States

The Center for Disease Control and Prevention announced Tuesday that the first case of the illness in the United States showed up in Washington state, in a male patient who is a US resident, according to CDC statement.

The virus, which was first identified in Wuhan, China, has infected more than 300 people in China and other Asian countries. Six patients have died. Airline stocks tumbled amid worries surrounding the outbreak's impact on global air travel.

The news of the spreading outbreak, along with a downgrade of Hong Kong's credit quality by ratings agency Moody's, weighed on global stocks overnight. US equities opened lower in New York, but losses were modest until the US case of the virus was reported.

The Dow was last 189 points, or 0.6%, in the red, extending its mild losses from earlier in the day. The S&P 500 and the Nasdaq Composite were both down 0.3%.

Meanwhile, Boeing stock dropped, making matters worse for the Dow.

The company's shares fell 5.5% on reports that it doesn't expect to receive Federal Aviation Administration approval for its troubled 737 Max jets fly again until the summer. The stock has since been halted.

Boeing has officially stopped making the 737 Max planes after announcing last year that it would pause production. The best-selling plane has been grounded since March last year following two fatal crashes.