"He's fine", Ms Buzyn said.
Lion Travel Service Co. indicated it will call off tours to China scheduled for between Sunday and Feb. 3, while Cola Tours said it will halt all China tours before the end of February.
She said that direct flights and trains from Wuhan would be blocked.
Because worldwide outbreaks occur so infrequently, health officials have only a couple of recent examples to draw on in studying how the coronavirus mutated to infect humans: the 2004 SARS and the 2015 MERS outbreaks. It can cause pneumonia, which has been deadly in some cases.
Wuhan said it would ban non-essential vehicles from its downtown starting Sunday to control the spread of the virus, further paralyzing a city of 11 million that has been on virtual lockdown since Thursday, with almost all flights canceled and checkpoints blocking the main roads leading out of town.
Indian authorities say an Indian nurse working in Saudi Arabia has also been infected, but Saudi health authorities say there has been no cases in the country so far.
NSW Chief Health Officer Dr Kerry Chant said that two of the three cases involved men who had returned to Australia on the 6 and 9 January.
USA coffee chain Starbucks said on Saturday that it was closing all its outlets in Hubei province for the week-long Lunar New Year holiday, following a similar move by McDonald's in five Hubei cities. Authorities cancelled a host of Lunar New Year events, and closed major tourist sites and movie theatres.
Health leaders from around the world are continuing to monitor the spread of the coronavirus, now responsible for the deaths more than 2 dozen people in China. The latest tally, from 29 provinces and cities across China, included 237 patients in serious condition.
The death toll from the 2019 novel coronavirus (2019-nCoV), which originated in the Chinese city of Wuhan in December, reached 41 in China as of Friday, 39 of which were in Hubei province.
The state Department of Health isn't disclosing where the man went between landing at Sea-Tac and being hospitalized.
Later on Saturday, authorities said three men in Sydney who had recently arrived from China had tested positive for the disease and were in isolation in local hospitals. Japan confirmed a third case, a Chinese tourist in her 30s who had arrived from Wuhan on Jan 18.
More than 20 hospitals in the city have posted statements asking for supplies such as latex gloves, protective goggles, surgical gowns and other medical gear to help deal with the thousands seeking screening for the disease, which can be transferred between people. 24, Hubei has received public donations of more than 1.2 million masks and 30 million yuan ($4.35 million), the official said. It is expected to be completed February 3, officials said.
But even for those free of infection, there has been an impact on daily life, as officials have urged people to avoid crowds and gatherings.
It is not clear how lethal the new coronavirus is, or even whether it is as risky as the ordinary flu, which kills tens of thousands of people every year in the US alone.
The rapid increase in reported deaths and illnesses does not necessarily mean the crisis is getting worse, but could reflect better monitoring and reporting of the newly discovered virus.