The novel virus, which was first identified last month in Wuhan, China, has so far infected more than 300 people and killed six, in an outbreak that has been reported in five countries -- now including the United States.
Health officials identified the infected person as a man in his 30s from Snohomish County, Washington.
The man recently traveled to China and arrived back in Seattle on Jan. 15.
The CDC says the risk to the general public is low. Authorities are working on notifying anyone who may have come in contact with the man.
It is unclear where and how they became infected, and if this person has transmitted the virus to anyone else in the United States.
A CDC team was sent to Washington state to assist Snohomish County and the Washington Department of Health.
Officials in China are racing to contain the spread of the new virus that has left at least six people dead and sickened more than 300, after it was confirmed the infection can spread between humans.
Wuhan, the central Chinese city where the coronavirus was first detected, announced a series of new measures Tuesday, including the cancellation of upcoming Lunar New Year celebrations, expected to attract hundreds of thousands of people.
Tour agencies have been banned from taking groups out of Wuhan and the number of thermal monitors and screening areas in public spaces will be increased. Traffic police will also conduct spot checks on private vehicles coming in and out of the city to look for live poultry or wild animals, after the virus was linked to a seafood and live animal market, according to a report by state media outlet the People's Daily, citing Wuhan's Municipal Health Commission.
The new measures come after Chinese President Xi Jinping ordered "resolute efforts to curb the spread" of the virus Monday.
There are now fears, however, that efforts to contain it are coming too late, hampered by a slow-moving Chinese bureaucracy which failed to put sufficient measures in place in time.
In the coming days, hundreds of millions of Chinese are expected to begin traveling across the country and overseas as the annual Lunar New Year break gets fully underway, compounding concerns of a further spike in cases.
Though infections were first detected in Wuhan in mid-December, infrared temperature screening areas were not installed in the city's airports and stations until January 14, according to state media.
On Tuesday, China's National Health Commission announced that it had received 291 confirmed cases of the Wuhan coronavirus, with 77 new cases reported on January 20.
The municipal health commissions of Zhejiang, Tianjin, Beijing and Shanghai also reported additional cases on Tuesday, pushing the number of infections up to 307.
Patients have been identified as having the virus in Hubei province, where Wuhan is located (270 cases), Beijing (10 cases); Guangdong province (14 cases); Shanghai (six cases); Zhejiang (five cases); and Tianjin (two cases). Suspected cases have also been reported in Yunnan, Sichuan, Guangxi and Shandong provinces.
The death toll rose to six Tuesday evening, after the Wuhan Municipal Health Commission confirmed that a 66-year-old male and a 48-year-old female died on January 20.
It added that 60 new cases were confirmed by the end of Monday in Wuhan city, where a 15-year-old is the youngest to be infected.