Authorities in China reported Wednesday that it has sickened almost 440 people and killed nine in their country.
He expects to see more cases in the country, but can't predict how severe they'll be.
There is a possibility that the Chinese authorities may request restraint if the virus spreads more during the massive travel rush that occurs during the Chinese New Year. It was only after a retired high-ranking physician spoke out that the true measure of authorities' concealment became known. He's reported to be in good condition at a Seattle-area hospital.
As they did during the SARS and Ebola outbreaks, health officials and scientists are tracking patients and testing samples of saliva and other fluids to determine the exact cause and severity of their ailments.
Tsai, speaking to reporters after Taiwan's Tuesday confirmation of its first case of the coronavirus, a woman returning to Taiwan from Wuhan, said China had to live up to its worldwide obligations. "This is what happens when you have respiratory diseases that can present at first with no symptoms".
The Centers for Disease Control and Prevention said in a statement that it "is working closely with the state of Washington and local partners". Residents said they were not overly concerned as long as they took preventive measures. "It's going to be just fine", the president said.
"But while the outbreak appears similar at the moment to SARS in the way that it has spread - first within China, then into neighboring areas, such as Hong Kong, Vietnam, Singapore and then to North America - we can not predict with any certainty how it will spread from now on", the expert underlined. The agency adds that this is a "rapidly evolving situation" and that the agency will continue to update the public "as circumstances warrant".
The CDC has begun screening arriving passengers at San Francisco (SFO), New York (JFK), Los Angeles (LAX), Atlanta (ATL), and Chicago (ORD) airports.
"Wildlife markets offer a unique opportunity for viruses to spill over from wildlife hosts", he said.
At a Wednesday news briefing, a reporter asked a National Health Commission official whether the government was hiding any information.
Thailand now has two cases, and South Korea and Japan each have one case.
The new measures come as throngs of people around the region prepare to travel for the Lunar New Year holidays starting this week.
Charly Bonnassie, a 24-year-old French student, told AFP he took a train leaving Wuhan Wednesday and said: "Everyone, meaning 100 percent, was wearing a mask".
The news comes after a French citizen had been reported to have suffered respiratory problems and other virus symptoms after returning to France from a trip to Wuhan, the Chinese city in which coronavirus appears to have originated. It has led to death in six cases in China.
The virus was found to have infected 15 health care workers, suggesting it can be transmitted from person to person, the Wuhan Municipal Health Commission said.
The World Health Organization will decide Wednesday whether to declare the novel virus an worldwide public health emergency, a designation used for complex epidemics that can cross borders.
Public health officials are taking steps to quickly diagnose and develop treatments for the coronavirus.
Here's a look at the other times the global health body has declared an emergency.