A staff member wearing protective gear is seen at a hospital in Wuhan, Hubei province, China January 22, 2020, in this still image taken from video. China News Service/via REUTERS TV.

Picture uploaded to social media on January 25, 2020 by the Central Hospital of Wuhan show medical staff holding Chinese Lunar New Year signs, in Wuhan, China. THE CENTRAL HOSPITAL OF WUHAN VIA WEIBO /via REUTERS

Pictures uploaded to social media on January 25, 2020 by the Central Hospital of Wuhan show medical staff attending to patients, in Wuhan, China. THE CENTRAL HOSPITAL OF WUHAN VIA WEIBO /via REUTERS

A picture released by the Central Hospital of Wuhan shows medical staff attending to patient at the The Central Hospital Of Wuhan Via Weibo in Wuhan, China on an unknown date. THE CENTRAL HOSPITAL OF WUHAN VIA WEIBO/Handout via REUTERS

A picture released by the Central Hospital of Wuhan shows medical staff attending to patient at the The Central Hospital Of Wuhan Via Weibo in Wuhan, China on an unknown date. THE CENTRAL HOSPITAL OF WUHAN VIA WEIBO/Handout via REUTERS

A medical staff attends a patient with pneumonia caused by the new coronavirus at the Zhongnan Hospital of Wuhan University, in Wuhan, Hubei province, China January 22, 2020. Picture taken January 22, 2020. cnsphoto via REUTERS.

People wearing masks shop at a supermarket on the second day of the Chinese Lunar New Year, following the outbreak of a new coronavirus, in Wuhan, Hubei province, China January 26, 2020. cnsphoto via REUTERS.

A street is seen in Wuhan, Hubei, China January 26, 2020 in this picture obtained from social media. WAYNE DUPLESSIS, WYATT DUPLESSIS, EMILY TJANDRA/via REUTERS

A picture released by the Central Hospital of Wuhan shows medical staff attending to patient at the The Central Hospital Of Wuhan Via Weibo in Wuhan, China on an unknown date. THE CENTRAL HOSPITAL OF WUHAN VIA WEIBO/Handout via REUTERS

Picture uploaded to social media on January 25, 2020 by the Central Hospital of Wuhan show medical staff, in Wuhan, China. THE CENTRAL HOSPITAL OF WUHAN VIA WEIBO /via REUTERS

A picture released by the Central Hospital of Wuhan shows medical staff attending to patient at the The Central Hospital Of Wuhan Via Weibo in Wuhan, China on an unknown date. THE CENTRAL HOSPITAL OF WUHAN VIA WEIBO/Handout via REUTERS

People walk past the closed Hankou Railway Station after the city was locked down following the outbreak of a new coronavirus in Wuhan, Hubei province, China January 23, 2020. China Daily via REUTERS

A worker sanitizes the square in front of the Hankou Railway Station, closed after the city of Wuhan was locked down following the outbreak of a new coronavirus, in Wuhan, Hubei province, China January 23, 2020. China Daily via REUTERS

A man stands in front of a screen showing that multiple departure flights have been cancelled after the city was locked down following the outbreak of a new coronavirus, at an airport in Wuhan, Hubei province, China January 23, 2020. cnsphoto via REUTERS.

People wearing masks shop at a market in Wuhan, Hubei province, China January 23, 2020, in this still image taken from video. China News Service/via REUTERS TV.

People wearing masks queue at a shop in Wuhan, Hubei province, China January 23, 2020, in this still image taken from video. China News Service/via REUTERS TV.

Image used for illustrative purpose. Pictures uploaded to social media on January 25, 2020 by the Central Hospital of Wuhan show medical staff attending to a patient, in Wuhan, China. THE CENTRAL HOSPITAL OF WUHAN VIA WEIBO /via REUTERS

Picture uploaded to social media on January 25, 2020 by the Central Hospital of Wuhan show medical staff attending to patients, in Wuhan, China. THE CENTRAL HOSPITAL OF WUHAN VIA WEIBO /via REUTERS

Street view after Wuhan government announced to ban non-essential vehicles in downtown area to contain coronavirus outbreak, on the second day of the Chinese Lunar New Year, in Wuhan, Hubei province, China January 26, 2020. cnsphoto via REUTERS.

Picture uploaded to social media on January 25, 2020 by the Central Hospital of Wuhan show medical staff, in Wuhan, China. THE CENTRAL HOSPITAL OF WUHAN VIA WEIBO /via REUTERS

Chinese paramilitary officers wearing masks stand guard at an entrance of the closed Hankou Railway Station after the city was locked down following the outbreak of a new coronavirus in Wuhan, Hubei province, China January 23, 2020. China Daily via REUTERS

People queue for receiving treatment at the fever outpatient department at the Wuhan Tongji Hospital in Wuhan, Hubei province, China January 22, 2020. Picture taken January 22, 2020. cnsphoto via REUTERS.

Excavators and bulldozers are seen at the construction site where the new hospital is being built to treat patients of a new coronavirus, following the outbreak and the city's lockdown, on the outskirts of Wuhan, China January 24, 2020. Picture taken January 24, 2020. cnsphoto via REUTERS.