This photo taken and handout on January 23, 2020 by Rome's Fiumicino Airport Authority (ADR) shows members of a health team getting ready to apply health measures and procedures against deadly SARS-like virus outbreak risks, after passengers landed at Rome's Fiumicino airport on a southern airlines flight from Wuhan, China. China banned trains and planes from leaving a major city at the centre of a virus outbreak on January 23, seeking to seal off its 11 million people to contain the contagious disease that has claimed 17 lives, infected hundreds and spread to other countries. (Photo by Aeroporto Di Roma/Handout via AFP Photo)





Security personnel wearing a mask stands guard outside the security check at the Beijing West Railway Station, in Beijing, China January 20, 2020. The outbreak, which began in the central Chinese city of Wuhan, also worried financial markets as investors recalled China's Severe Acute Respiratory Syndrome (SARS) epidemic in 2002-2003, a coronavirus outbreak that killed nearly 800 people. (Photo by Reuters/China Stringer Network)





A worker in a protective suit is seen at the closed seafood market in Wuhan, Hubei province, China January 10, 2020. The seafood market is linked to the outbreak of pneumonia caused by the new strain of coronavirus, but some patients diagnosed with the new coronavirus deny exposure to this market. The virus struck as millions of Chinese prepared to travel for the Lunar New Year, heightening contagion risks. Many in China scrambled to buy face masks to protect themselves from the previously unknown, flu-like infection. (Photo by Reuters/China Stringer Network)





Medical staff transfer a patient at the Jinyintan hospital, where the patients with pneumonia caused by the new strain of coronavirus are being treated, in Wuhan, Hubei province, China January 20, 2020. The death toll from a mysterious flu-like virus in China climbed to six as new cases surged beyond 300 and authorities fretted about the added risk from millions of Chinese traveling for the Lunar New Year holiday. (Photo by Reuters/China Stringer Network)





People wearing masks walk down the steps at a subway station in Beijing, China on January 21, 2020. (Photo by Tingshu Wang/Reuters)





A woman and a child wearing masks stand on a street in Hangzhou, Zhejiang province, China on January 21, 2020. (Photo by Reuters/China Daily)





An employee stands behind a door as the train arrives at a railway station while the annual Spring Festival travel rush begins ahead of the Chinese Lunar New Year, in Baoding, Hebei province, China on January 10, 2020. (Photo by Jason Lee/Reuters)





A man wearing a protective mask sits on luggage as he travels on the subway in Shanghai on January 22, 2020. A new virus that has killed nine people, infected hundreds and already reached the United States could mutate and spread, China warned January 22, as authorities scrambled to contain the disease during the Lunar New Year travel season. (Photo by Hector Retamal/AFP Photo)





A child wears mask to prevent an outbreak of a new coronavirus at the Hong Kong West Kowloon High Speed Train Station, in Hong Kong, China on January 23, 2020. (Photo by Tyrone Siu/Reuters)





Staff members check body temperatures of the passengers arriving from the train from Wuhan to Hangzhou, at Hangzhou Railway Station ahead of the Chinese Lunar New Year in Zhejiang province, China January 23, 2020. China put millions of people on lockdown on Thursday in two cities at the epicenter of a coronavirus outbreak, as authorities around the world worked to prevent a global pandemic as hundreds of millions of Chinese travel at home and abroad during the Lunar New Year. (Photo by Reuters/China Daily)





In this Tuesday, January 21, 2020, photo, travelers wearing face masks walk with their luggage at Hankou Railway Station in Wuhan in southern China's Hubei province. The U.S. on Tuesday reported its first case of a new and potentially deadly virus circulating in China, saying a Washington state resident who returned last week from the outbreak's epicenter was hospitalized near Seattle. (Photo by Chinatopix via AP Photo)





Staff sell masks at a Yifeng Pharmacy in Wuhan, Chin, Wednesday, January 22, 2020. Pharmacies in Wuhan are restricting customers to buying one mask at a time amid high demand and worries over an outbreak of a new coronavirus. The number of cases of the new virus has risen over 400 in China and the death toll to 9, Chinese health authorities said Wednesday. (Photo by Dake Kang/AP Photo)





People wear protective face masks on a street in Hong Kong, Friday, January 24, 2020. China closed off a city of more than 11 million people Thursday, halting transportation and warning against public gatherings, to try to stop the spread of a deadly new virus that has sickened hundreds and spread to other cities and countries in the Lunar New Year travel rush. (Photo by Achmad Ibrahim/AP Photo)





Travelers wear face masks as they stand in the arrivals area at Beijing Capital International Airport in Beijing, Thursday, January 23, 2020. China closed off a city of more than 11 million people Thursday, halting transportation and warning against public gatherings, to try to stop the spread of a deadly new virus that has sickened hundreds and spread to other cities and countries in the Lunar New Year travel rush. (Photo by Mark Schiefelbein/AP Photo)





A policeman uses a digital thermometer to take a driver's temperature at a checkpoint at a highway toll gate in Wuhan in central China's Hubei Province, Thursday, January 23, 2020. China closed off a city of more than 11 million people Thursday in an unprecedented effort to try to contain a deadly new viral illness that has sickened hundreds and spread to other cities and countries amid the Lunar New Year travel rush. (Photo by Chinatopix via AP Photo)





The resident wear masks to buy vegetables in the market on January 23th, 2020 in Wuhan, Hubei£¬China. Flights, trains and public transport including buses, subway and ferry services have been temporarily closed and officials have asked residents told to stay in town in order to help stop the outbreak of a strain of coronavirus that has killed 17 people and infected over 500 in places as far away as the United States. This week marks the start of Chinese Lunar New Year holiday, the busiest season for Chinese travellers. (Photo by Getty Images/China Stringer Network)





Patients queue up to seek treatment in Wuhan Tongji Hospital Fever Clinic, in Wuhan City, Hubei Province, China, 22 January 2020 (issued 23 January 2020). The outbreak of coronavirus has so far claimed 17 lives and infected more than 550 others, according to media reports. Authorities in Wuhan announced on 23 January, a complete travel ban on residents of Wuhan in an effort to contain the spread of the virus. (Photo by EPA/EFE/China Stringer Network)





Workers stand amid heavy equipment at a construction site for a field hospital in Wuhan in central China's Hubei Province, Friday, January 24, 2020. China is swiftly building a hospital dedicated to treating patients infected with a new virus that has killed 26 people, sickened hundreds and prompted unprecedented lockdowns of cities home to millions of people during the country's most important holiday. (Photo by Chinatopix via AP Photo)





Heavy equipment works at a construction site for a field hospital in Wuhan in central China's Hubei Province, Friday, January 24, 2020. China is swiftly building a 1,000-bed hospital dedicated to patients infected with a new virus that has killed 26 people, sickened hundreds and prompted unprecedented lockdowns of cities during the country's most important holiday. (Photo by Chinatopix via AP Photo)





Chinese passengers, most wearing masks, arrive to board trains before the annual Spring Festival at a Beijing railway station on January 23, 2020 in Beijing, China. The number of cases of a deadly new coronavirus rose to over 500 in mainland China Wednesday as health officials locked down the city of Wuhan in an effort to contain the spread of the pneumonia-like disease. Medicals experts have confirmed that the virus can be passed from human to human. In an unprecedented move, Chinese authorities put travel restrictions on the city of 11 million and two other neighboring cities, preventing people from leaving after 10 AM local time Thursday. The number of those who have died from the virus in China climbed to at least 17 on Thursday and cases have been reported in other countries including the United States,Thailand, Japan, Taiwan and South Korea. (Photo by Kevin Frayer/Getty Images)





A militia member checks the body temperature of a driver on a vehicle at an expressway toll gate in Wuhan in central China's Hubei province, 23 January 2020, in a bid to contain the spread of the new coronavirus. (Photo by Yuan Zheng/EPA/EFE)





A police officer wearing a protective mask walks past the portrait of late communist leader Mao Zedong (not pictured) at Tiananmen Gate in Beijing on January 23, 2020. Large-scale Lunar New Year events in Beijing have been cancelled as part of national efforts to control the spread of a new SARS-like virus, city authorities announced on January 23. (Photo by Nicolas Asfouri/AFP Photo)