The man is in his 20s and lives in Boston, the state's Department of Health said in a press release on Saturday. The Centers for Disease Control and Prevention notified health officials about the case late Friday evening, the release stated, adding that the risk to the public is low.
This is the eighth confirmed case of coronavirus in the United States. The other cases are two in Illinois, three in California, and one each in Washington state and Arizona.
The man had recently traveled to Wuhan, the epicenter of the virus, and sought medical treatment soon after returning to Massachusetts, the Department of Health said in its release. He has been in isolation ever since and will remain isolated until public health officials clear him.
People known to have been in close contact with him are being monitored for symptoms, officials said.
"We are grateful that this young man is recovering and sought medical attention immediately," said Massachusetts Public Health Commissioner Monica Bharel. "Massachusetts has been preparing for a possible case of this new coronavirus, and we were fortunate that astute clinicians took appropriate action quickly. Again, the risk to the public from the 2019 novel coronavirus remains low in Massachusetts."
Gov. Charlie Baker in a tweet Saturday urged the public to take "the same precautions they do to prevent the spread of the cold and flu."
On Saturday, the New York City Department of Health announced that a person in the city has been identified for testing. Health officials said the person, who is under 40 years old, had recently traveled from China and "presented with fever and cough or shortness of breath without another common cause." Testing to determine whether the person has the first confirmed case of coronavirus in New York will take 36 to 48 hours.
On Friday, Secretary of Health and Human Services Alex Azar declared a public health emergency in the U.S. over the virus.
Starting Sunday at 5 p.m. ET, all passengers on flights to the U.S. who have been in Hubei province in the last 14 days will be subject to up to 14 days of quarantine, officials said. Wuhan is located in Hubei.
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U.S. citizens who have been in the rest of mainland China will be screened at one of seven airports for risk and signs of possible symptoms. Those airports are New York, San Francisco, Seattle, Honolulu, Los Angeles, Chicago and Atlanta.
The White House said that it will not allow anyone who has been in China recently to enter the U.S. because they pose a risk of transmitting the virus. The policy will apply to foreign nationals — other than immediate family members of U.S. citizens and permanent residents — who have traveled to China within the last 14 days.