Here is what we know:

- There are 131 confirmed cases in 23 countries and regions outside mainland China, including Australia, Britain, France, Germany, Hong Kong, Japan, Thailand and the United States.

- No deaths have been reported outside China.

- The World Health Organization declared the outbreak a public health emergency of international concern on Thursday. [nL4N29Y5DF]

- The United States reported its first case of person-to-person transmission. Germany, Japan, Thailand, Vietnam and South Korea have also recorded similar transmissions, which suggest greater potential for the virus to spread.

- Several Chinese cities have levied strict travel curbs.

- The U.S. State Department told Americans not to travel to China.

- The Trump administration declared a public health emergency over the coronavirus outbreak and said it would take the extraordinary step of barring entry to the United States of foreign nationals who have traveled to China.

- Japan advised its citizens to put off non-urgent travel to China and brought forward special measures to stem the spread of the coronavirus.

- Russia reported its first two cases of coronavirus and restricted direct flights to China, its biggest trade partner.

- Global airlines have suspended or scaled back direct flights to China's major cities.

- Countries including Australia, Canada, France, Germany, Indonesia, Italy, Japan, Singapore, South Korea and the United States are working to evacuate citizens from Wuhan or have already started.

- A charter flight carrying 368 South Koreans from Wuhan landed in Seoul. The evacuees were taken to quarantine centres.

- A plane carrying 83 British and 27 other foreign nationals left Wuhan, the British government said.

- Authorities in Myanmar turned back a China Southern flight from Guangzhou with almost everyone on board after one of the passengers was found with flu symptoms similar to the coronavirus, a government spokesman said.

- Hong Kong leader Carrie Lam rejected calls from a medical union to close the border with mainland China to contain the spread of the coronavirus.

- China's aviation authority sent two flights to bring back its tourists stranded in Thailand and Malaysia.

- China will release winter and spring vegetable reserves in major northern cities to ease supply shortages amid the new coronavirus outbreak, state news agency Xinhua reported.

- The Chinese Football Association said it would postpone domestic games in 2020.

- The World Athletics Indoor Championships scheduled in the Chinese city of Nanjing in March have been postponed until 2021.

- The coronavirus should have little impact on the U.S. economy, President Donald Trump's chief economic adviser said.

- China's capital Beijing said that companies in the province will postpone reopening until Feb. 10 in order to help prevent the spread of a new coronavirus, government newspaper Beijing Daily reported.

- Some experts believe the virus is not as dangerous as the 2002-03 Severe Acute Respiratory Syndrome (SARS) that killed nearly 800 people, or the Middle East Respiratory Syndrome (MERS), which has killed more than 700 people since 2012.

(Compiled by Stephen Coates; Editing by Christopher Cushing, Timothy Heritage and Diane Craft)