"Despite the case that we are reporting the first instance of person-to-person transmission in the United States, it is important to note that these two individuals were in close contact", said Dr. Nancy Messonnier, director of the CDC's National Center for Immunization and Respiratory Diseases. Wuhan is the capital of Hubei Province. There have been some speculations that they might have infected other passengers on the plane en route to Tokyo. South Korea, Britain, New Zealand, Australia, Singapore and other European countries were also trying to get their citizens out.
Samples of their tests are being sent to the US Centers for Disease Control and Prevention, which will determine whether they are free of the virus. All, including the crew, will now be put under quarantine for 14 days.
Meanwhile, the evacuations of hundreds of foreign nationals from Wuhan to their respective countries has begun.
Residents scuffle with police officers during a rally to protest the government's decision to quarantine South Koreans returning from Wuhan in their home town in Jincheon, South Korea, Thursday, Jan. 30, 2020.
Canada, the Philippines and Malaysia have also announced plans to fly their citizens out of Wuhan.
Official alarm: After an hours long debate today, a panel of health experts called the International Health Regulations Emergency Committee finally declared an emergency.
She said that there were at least 243 Indonesians in areas declared to be in lockdown, the majority of whom were in Wuhan.
Like the similar Sars and influenza viruses, the new coronavirus is thought to be particularly a risk for elderly and people with pre-existing illnesses.
"We have to be balanced in our approach, we will take all public health measures necessary to protect the American public, so we brief the president as we do ourselves on the current epidemiological information on the spread of the virus, these steps happening internationally, and our preventive preparedness steps that we're taking in the United States".
The patient and anyone in contact with them should follow strict hygiene, including diligent hand washing, and cough hygiene. "But you are still re-circulating a lot of the air, and no matter how good the filtration system is, it may not be able to filter out something as small as a virus", Driskill told Al Jazeera.
Tedros Adhanom Ghebreyesus, Director General of the World Health Organisation says there is no reason to restrict travel to China. The much faster pace of coronavirus infections, however, has public health officials in China and across the world concerned.
Almost 200 Americans, mostly diplomats and families, airlifted from Wuhan on Wednesday, will stay isolated at a US military base in California for at least 72 hours, officials said. Her husband, who had been in close contact with her while she had been presenting symptoms, is being monitored, and has presented symptoms as well, leading health officials to determine that it is the first person-to-person transmission of 2019-nCoV within the US.
However, Zeng said that he could not rule out other factors, such as "some hesitation in the decision-making process", and "whether the government had confidence in itself".
At present, most of the infections detected in other countries are linked back directly to Wuhan, Cowling said.
Statistics from China indicate that just over 2% of people infected have died, suggesting that the virus may be less deadly than the coronaviruses behind 2002-2003 Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS).