In one of the first public briefings since the beginning of the outbreak, National Health Commission vice-minister Li Bin said there was evidence that the disease was "mainly transmitted through the respiratory tract".
The World Health Organization is due to meet to decide whether to declare the outbreak a global public health emergency but officials in the United States and Australia say they now believe the risk to the general populace is low.
"[He is] now hospitalized out of an abundance of caution and for observation", Lindquist said. The CDC and Washington state are now tracing the people he was in contact with to see if he might have spread the disease to someone else.
Due to concerns about the virus spreading human-to-human, the CDC has activated an emergency response in the U.S. As of January 17, people flying from Wuhan, China to the U.S. are being routed through specific airports that have advanced screening for the virus.
Also on Tuesday, Chinese health officials confirmed that more than 300 cases of infection have now been identified, including six deaths, CNN reported.
Officials have said the virus probably spread from animals to people, but this week Chinese officials said they've concluded it also can spread from person to person.
It is still not clear how powerful the coronavirus is compared with the outbreak of the severe acute respiratory syndrome in 2002-2003, but experts say - albeit with caution - that early symptoms appear to be less severe than SARS.
The U.S. patient said that he did not visit any markets in Wuhan.
On Jan. 17, the CDC deemed the risk to USA citizens to be low, but four days later announced that the first case had been confirmed stateside. Symptoms of the virus can include difficulty breathing, fever, and cough.
The WHO will hold a meeting on Wednesday to determine whether the outbreak constitutes a "public health emergency of worldwide concern" and if so, what should be done to manage it.
During the upcoming Spring Festival holiday, densely populated places including train stations, airports and shopping malls, as well as buses and trains, should adopt measures of ventilation, sterilization and temperature screening according to local situations, the NHC said.
New Zealand has followed a similar route to Australia by increasing the visibility of information via health advice cards, Dr McElnay said.
They also include an extra health screening question to be asked by Canada Border Services Agency (CBSA) agents to arriving travellers.
Gao said officials are working on the assumption that the outbreak resulted from human exposure to wild animals that were being traded in illegally at a market in Wuhan and that the virus is mutating.
A total of 291 confirmed cases of new coronavirus-related pneumonia and 54 suspected cases have been reported in China by the end of Monday.
- Do not make direct contact with persons who are experiencing symptoms of respiratory tract infections.