In Hunt for Covid-19 Origin, Patient Zero Points to Second Wuhan Market


World Health Organization investigators are seeking information about a second food market in the Chinese city of Wuhan after the first officially confirmed Covid-19 case, dubbed patient zero, told them his parents had shopped there.

Chinese authorities have said since early last year that the first confirmed victim was a Wuhan resident surnamed Chen who fell sick on Dec. 8, 2019, and had no connection to the Huanan seafood market, which was tied to many of the early infections.

That case, and more recent evidence, led a WHO team probing the pandemic’s origins to conclude that the virus might have first jumped from an animal to a human earlier, and elsewhere, and been spreading throughout Wuhan by the time an outbreak at the Huanan market occurred.

The putative patient zero met the WHO investigators during their recent four-week visit to Wuhan, and told them that his parents had visited another local community food market, according to three team members.

The revelation came at the end of the man’s meeting with the WHO investigators and they were unable to identify the market or obtain further details, the team members said. They declined to comment further.

The investigators’ interest in patient zero’s parents was first reported by CNN in an interview with

Peter Daszak,

a WHO team member who said the parents had tested negative but Chinese authorities should still trace their contacts at the market. He didn’t respond to requests for comment.

The Huanan seafood market in Wuhan has been tied to many of the first Covid-19 infections.



Photo:

Getty Images/Getty Images

It couldn’t be determined when the parents were tested, and whether they had PCR tests, which detect current but not past infection, or antibody screenings, which can reveal past infection but can also fade to undetectable levels over time. Both types of tests would have been unavailable in early December 2019 because the virus hadn’t yet been identified.

Members of the WHO team want to identify the market to find out if any wild animals were sold there and establish whether any more of the 174 confirmed cases from December 2019, or potential cases from earlier, had connections to it.

The team and its Chinese counterparts have already established that some of the 174 had connections to markets other than Huanan, although they haven’t named those places.

Wuhan, with a population of 11 million, has some 400 food markets, according to local authorities. Residents say several of them have sold wildlife as meat or for traditional medicine, and vendors say goods were often traded between Huanan and other markets.


There is clear evidence of simultaneous transmission of the virus in other places outside the market


— Thea Fischer, WHO team member

The lack of details surrounding the first known case in a pandemic that has now killed more than two million shows the scale of work that still needs to be done to reconcile the Huanan market outbreak in December with other data showing the virus infected people elsewhere in Wuhan at the same time and may have started spreading in November or October 2019.

“We need more studies of the early cases,” Peter Ben Embarek, the WHO team leader, told the Journal. “This is in our recommendations for new work.”

China’s foreign ministry and National Health Commission didn’t respond to requests for comment.

The episode “highlights the need for the WHO team to continue their China segment of the investigation,” said

Yanzhong Huang,

senior fellow for global health at the Council on Foreign Relations in New York. “Given the complexity and importance of their work, one month is not enough to draw any conclusive findings.”

The WHO is set in the coming days to publish a summary report on the Wuhan mission, which is expected to include a series of recommendations for studies on the origins of the pandemic. The report will call for further scrutiny of those earliest cases and potential cases—including the putative patient zero and his relatives, according to WHO team members.

A full report on the trip is expected weeks later, they say.

Meanwhile, international controversy over the pandemic’s origins has reignited, with the U.S. expressing concern over a lack of transparency after The Wall Street Journal reported that China hadn’t shared raw data on confirmed or potential early cases.

WHO team members during their mission to Wuhan.



Photo:

thomas peter/Reuters

Beijing responded by accusing Washington of undermining the WHO and repeating its assertion that the virus could have originated in another country and spread to Wuhan via imported frozen food.

Still, Liang Wannian, the head of a Covid-19 expert panel for China’s National Health Commission, acknowledged during a news conference at the end of the WHO mission that some of the first 174 confirmed cases “were associated with other markets” in Wuhan.

Chinese authorities initially thought the Huanan market was the source of the outbreak because many of the earliest identified cases had visited or worked there, because there were stalls there selling the kind of wildlife that spread coronaviruses in the past and because environmental samples taken there tested positive for SARS-CoV-2.

The World Health Organization’s mission to Wuhan said the coronavirus most likely spread naturally to humans through an animal. WSJ’s Jeremy Page reports on what scientists learned during their weekslong investigation. Photo: Thomas Peter/Reuters

WHO scientists and other experts have long believed the new coronavirus most likely originated in a bat and spread to humans via another animal, probably on a farm or in a market.

The WHO investigators say they confirmed during their visit that there were at least two types of animals that can carry the new coronavirus at the Huanan market, ferret badgers and rabbits, presenting one possible pathway for how the pandemic began.

They say they have yet to establish what other animals were sold, legally or illegally, but supply chains for the stalls in question lead back to parts of southern China where the closest known relatives of SARS-CoV-2 have been found in bats.

At the same time, there are indications the virus was already spreading widely throughout the city within days of the first known cases in the market, suggesting the outbreak could have begun somewhere else and spread to the Huanan market.

“There is clear evidence of simultaneous transmission of the virus in other places outside the market,” Thea Fischer, a Danish epidemiologist on the WHO team, told reporters in Wuhan. “It seems less likely that the market is the source of the virus epidemic.”

Investigating the Origin of Covid-19

Dr. Ben Embarek told CNN in an interview this month that patient zero was an office worker in his 40s in a private company and had no recent travel history. “He has a very, in a way, dull and normal life—no hiking-in-the-mountains type of things,” Dr. Ben Embarek said.

Dr. Daszak said the man’s main hobby was surfing the internet.

Some researchers have pointed to an elderly man who fell sick on Dec. 1, 2019, as a possible infection before patient zero’s, but a doctor who treated him said he had other chronic illnesses and couldn’t speak, and his exact date of symptoms onset was unclear as it was estimated by relatives.

Write to Jeremy Page at jeremy.page@wsj.com, Drew Hinshaw at drew.hinshaw@wsj.com and Betsy McKay at betsy.mckay@wsj.com

Copyright ©2020 Dow Jones & Company, Inc. All Rights Reserved. 87990cbe856818d5eddac44c7b1cdeb8



Source link

Leave a Reply

Your email address will not be published. Required fields are marked *