EXPLAINER: What the WHO coronavirus experts learned in Wuhan
A worker wearing a mask, watches from inside a hospital across the Wuhan Center for Disease Control and Prevention after the World Health Organization team arrive to make a field visit in Wuhan in central China's Hubei province on Monday, Feb. 1, 2021. (AP Photo/Ng Han Guan)

A worker wearing a mask, watches from inside a hospital across the Wuhan Center for Disease Control and Prevention after the World Health Organization team arrive to make a field visit in Wuhan in central China's Hubei province on Monday, Feb. 1, 2021. (AP Photo/Ng Han Guan)

Feb. 01, 2021 05:38 AM EST
Members of the World Health Organization team including Ken Maeda right, Peter Daszak, third from left and Vladmir Dedkov, fourth from left, leave after attending an exhibition about the fight against the coronavirus in Wuhan in central China's Hubei province on Saturday, Jan. 30, 2021. The World Health Organization team investigating the origins of the coronavirus pandemic visited another Wuhan hospital that had treated early COVID-19 patients on their second full day of work on Saturday. (AP Photo/Ng Han Guan)

Members of the World Health Organization team including Ken Maeda right, Peter Daszak, third from left and Vladmir Dedkov, fourth from left, leave after attending an exhibition about the fight against the coronavirus in Wuhan in central China's Hubei province on Saturday, Jan. 30, 2021. The World Health Organization team investigating the origins of the coronavirus pandemic visited another Wuhan hospital that had treated early COVID-19 patients on their second full day of work on Saturday. (AP Photo/Ng Han Guan)

Jan. 30, 2021 04:57 AM EST
Peter Ben Embarek and Thea Koelsen Fischer of the World Health Organization team prepares to board a plane from the tarmac at the airport to leave at the end of the WHO mission in Wuhan, China, Wednesday, Feb. 10, 2021. (AP Photo/Ng Han Guan)

Peter Ben Embarek and Thea Koelsen Fischer of the World Health Organization team prepares to board a plane from the tarmac at the airport to leave at the end of the WHO mission in Wuhan, China, Wednesday, Feb. 10, 2021. (AP Photo/Ng Han Guan)

Feb. 10, 2021 07:48 AM EST
Peter Daszak of the World Health Organization leaves in a car past a row of security personnel at the Hubei Center for Disease Control and Prevention after a field visit in Wuhan in central China's Hubei province on Monday, Feb. 1, 2021. (AP Photo/Ng Han Guan)

Peter Daszak of the World Health Organization leaves in a car past a row of security personnel at the Hubei Center for Disease Control and Prevention after a field visit in Wuhan in central China's Hubei province on Monday, Feb. 1, 2021. (AP Photo/Ng Han Guan)

Feb. 01, 2021 05:38 AM EST
Thea Koelsen Fischer of the World Health Organization team speaks to journalists outside after a WHO-China Joint Study Press Conference held at the end of the WHO mission in Wuhan, China, Tuesday, Feb. 9, 2021. (AP Photo/Ng Han Guan)

Thea Koelsen Fischer of the World Health Organization team speaks to journalists outside after a WHO-China Joint Study Press Conference held at the end of the WHO mission in Wuhan, China, Tuesday, Feb. 9, 2021. (AP Photo/Ng Han Guan)

Feb. 10, 2021 07:48 AM EST
Thea Koelsen Fischer of the World Health Organization team arrive at the VIP terminal of the airport to leave at the end of the WHO mission in Wuhan, China on Wednesday, Feb. 10, 2021. (AP Photo/Ng Han Guan)

Thea Koelsen Fischer of the World Health Organization team arrive at the VIP terminal of the airport to leave at the end of the WHO mission in Wuhan, China on Wednesday, Feb. 10, 2021. (AP Photo/Ng Han Guan)

Feb. 10, 2021 07:47 AM EST
Workers wave off a team of experts from the World Health Organization who ended their quarantine and left the quarantine hotel in a bus in Wuhan in central China's Hubei province on Thursday, Jan. 28, 2021. The WHO team emerged from quarantine to start field work in a fact-finding mission on the origins of the virus that caused the COVID-19 pandemic. (AP Photo/Ng Han Guan)

Workers wave off a team of experts from the World Health Organization who ended their quarantine and left the quarantine hotel in a bus in Wuhan in central China's Hubei province on Thursday, Jan. 28, 2021. The WHO team emerged from quarantine to start field work in a fact-finding mission on the origins of the virus that caused the COVID-19 pandemic. (AP Photo/Ng Han Guan)

Jan. 28, 2021 03:37 AM EST
FILE - In this Jan. 31, 2021, file photo, the World Health Organization team is briefed outside of the Huanan Seafood Market on the third day of their field visit in Wuhan, China. The market, which had a cluster of cases at the start of the outbreak, was initially suspected as the place where people first became infected. The discovery of earlier cases has all but ruled out that theory, but researchers still want to know how this early cluster happened. (AP Photo/Ng Han Guan, File)

FILE - In this Jan. 31, 2021, file photo, the World Health Organization team is briefed outside of the Huanan Seafood Market on the third day of their field visit in Wuhan, China. The market, which had a cluster of cases at the start of the outbreak, was initially suspected as the place where people first became infected. The discovery of earlier cases has all but ruled out that theory, but researchers still want to know how this early cluster happened. (AP Photo/Ng Han Guan, File)

Feb. 10, 2021 10:10 AM EST
A security official moves journalists away from the Wuhan Institute of Virology after a World Health Organization team arrived for a field visit in Wuhan in China's Hubei province on Wednesday, Feb. 3, 2021. The WHO team is investigating the origins of the coronavirus pandemic has visited two disease control centers in the province. (AP Photo/Ng Han Guan)

A security official moves journalists away from the Wuhan Institute of Virology after a World Health Organization team arrived for a field visit in Wuhan in China's Hubei province on Wednesday, Feb. 3, 2021. The WHO team is investigating the origins of the coronavirus pandemic has visited two disease control centers in the province. (AP Photo/Ng Han Guan)

Feb. 03, 2021 08:20 AM EST
A member of a World Health Organization team is seen wearing protective gear during a field visit to the Hubei Animal Disease Control and Prevention Center for another day of field visit in Wuhan in central China's Hubei province Tuesday, Feb. 2, 2021. The WHO team is investigating the origins of the coronavirus pandemic has visited two disease control centers in the province. (AP Photo/Ng Han Guan)

A member of a World Health Organization team is seen wearing protective gear during a field visit to the Hubei Animal Disease Control and Prevention Center for another day of field visit in Wuhan in central China's Hubei province Tuesday, Feb. 2, 2021. The WHO team is investigating the origins of the coronavirus pandemic has visited two disease control centers in the province. (AP Photo/Ng Han Guan)

Feb. 01, 2021 08:59 PM EST
Security personnel block the windows to prevent journalists from looking in as a World Health Organization team visits the Service Center for Party Members and Residents of Jiangxinyuan Community in Wuhan in central China's Hubei province on Thursday, Feb. 4, 2021. (AP Photo/Ng Han Guan)

Security personnel block the windows to prevent journalists from looking in as a World Health Organization team visits the Service Center for Party Members and Residents of Jiangxinyuan Community in Wuhan in central China's Hubei province on Thursday, Feb. 4, 2021. (AP Photo/Ng Han Guan)

Feb. 04, 2021 08:41 AM EST
Marion Koopmans, right, and Peter Ben Embarek, center, of the World Health Organization team say farewell to their Chinese counterpart Liang Wannian, left, after a WHO-China Joint Study Press Conference held at the end of the WHO mission in Wuhan, China, Tuesday, Feb. 9, 2021. (AP Photo/Ng Han Guan)

Marion Koopmans, right, and Peter Ben Embarek, center, of the World Health Organization team say farewell to their Chinese counterpart Liang Wannian, left, after a WHO-China Joint Study Press Conference held at the end of the WHO mission in Wuhan, China, Tuesday, Feb. 9, 2021. (AP Photo/Ng Han Guan)

Feb. 09, 2021 08:34 AM EST
Peter Ben Embarek, of the World Health Organization team holds up a chart showing pathways of transmission of the virus during a joint press conference held at the end of the WHO mission in Wuhan, China, Tuesday, Feb. 9, 2021. (AP Photo/Ng Han Guan)

Peter Ben Embarek, of the World Health Organization team holds up a chart showing pathways of transmission of the virus during a joint press conference held at the end of the WHO mission in Wuhan, China, Tuesday, Feb. 9, 2021. (AP Photo/Ng Han Guan)

Feb. 09, 2021 05:33 AM EST