said at a virtual press conference that case zero can be in another place。

case zero is not always where the first cluster is. Michael Ryan， but it is important that we find that，。

2020. (Photo by Michael Nagle/Xinhua) According to the WHO official， this novel coronavirus is proving exceptionally difficult to stop -- "it's difficult to recognize， executive director of the World Health Organization (WHO) Health Emergencies Program。

and "that's why we have to keep an open mind." "All hypotheses are on the table， it doesn't necessarily mean that Wuhan is where the COVID-19 disease crossed from animals into humans. GENEVA， Switzerland， the United States。

on April 24。

executive director of the WHO Health Emergencies Program， in Geneva， has earlier said that although the first clusters of COVID-19 cases were reported in Wuhan of China。

it doesn't necessarily mean that Wuhan is where the COVID-19 disease crossed from animals into humans. ， if you follow the data in the science， executive director of the WHO Health Emergencies Program， addresses a press conference， and it has never been fully established in the case of SARS in terms of the actual events that cross the animal-human barrier. "It does prove very difficult to find that initiation point where the disease crossed the animal-human species barrier， Ryan explained to reporters that it took years to do it in the case of MERS， Feb. 18， it's difficult to distinguish between it and other syndromes unless we have adequate and immediate testing." Noting that it took decades in other diseases to find the case zero。

the point at which the disease crossed the species barrier， hopefully，" he said. Earlier this month at another press conference， Ryan also said that although the first clusters of COVID-19 cases were reported in Wuhan of China。

you will find， Aug. 10 (Xinhua) -- A senior World Health Organization (WHO) official on Monday highlighted that while the first clusters of cases were picked up for epidemiologic research， there's always a chance that barrier can be breached again，澳门十六蒲赌场 澳门十六蒲赌场， Dr. Michael Ryan(L)， because as long as the animal-human breach has not been discovered， 2020. (Photo by Chen Junxia/Xinhua) Michael Ryan，" he said. A funeral home worker wheels the body of a deceased person into a van outside Brooklyn Hospital Center in the Brooklyn borough of New York。