The first case of Wuhan coronavirus in the U.S. was detected in Washington state, according to the nation's health agency Tuesday.

The infected male patient from Snohomish County is in isolation at Providence Regional Medical Center in Everett. He returned Jan. 15 from Wuhan, China, where the outbreak began.

The patient in his 30s experienced symptoms after returning from the trip to the region and was diagnosed with pneumonia last week. His infection with was confirmed Monday.

CNN and the New York Times were first to report the case.

"While originally thought to be spreading from animal-to-person, there are growing indications that limited person-to-person spread is happening," said the Centers for Disease Control and Prevention (CDC) in a release. "It’s unclear how easily this virus is spreading between people."

Also known as 2019-nCoV, the coronavirus, which causes pneumonia-like symptoms, was identified in December in Wuhan, China.

Symptoms with the virus include fever, cough and trouble breathing.

The CDC said it is working closely with the state of Washington and local partners and sent a team to support an ongoing investigation there.

On Friday, the agency began screening travelers from Wuhan for symptoms of the respiratory virus at San Francisco, New York and Los Angeles airports.

This week, it will add entry health screening at Atlanta and Chicago airports.

At least six people have died and nearly 300 cases reported this month in China. Beyond China, the virus has affected people in Taiwan, Japan and South Korea.