Skip to content
China to test thousands of blood samples from Wuhan in Covid-19 probe


The store, which can hold up to 200,000 samples, including those from the last months of 2019, was identified in February this year by the World Health Organization panel of investigators as a possible source of key information that could help determine when and where the virus first spread to humans. .

The samples are being held at the Wuhan Blood Center and are expected to extend into 2019, providing real-time tissue samples from a large section of the population in the Chinese city where SARS-CoV-2 is believed to have first infected human beings. humans.

The blood bank samples have been kept for two years, Chinese officials said, in case they are needed as evidence in legal proceedings relating to the donated blood from which they came.

This two-year waiting period will soon expire for the key months of October and November 2019, when most experts believe the virus could have first infected humans. An official from China’s National Health Commission told CNN that preparation for the tests is currently underway and confirmed testing will take place once the two-year limit is reached.

“This provides the closest-to-the-world samples we’ve seen among the real-time samples to help us understand the timing of the outbreak,” said Yanzhong Huang, senior researcher for global health at the Council on Foreign Relations.

They will “absolutely contain vital signs,” said Maureen Miller, associate professor of epidemiology at Columbia University. She urged China to allow foreign experts to observe the process. “No one will believe the results reported by China unless there are at least qualified observers,” she said.

The head of the Chinese team working on the WHO investigation, Liang Wannian, first told a press conference in July that China would test the samples, adding that once Chinese experts “Will have the results, they will hand them over to both Chinese and foreign experts.” teams. “

Liang said the samples came from the opening tube of a donor blood bag, sealed and then stored, and that Chinese experts had “made several evaluations and evaluations on the testing methods and plan of action, which will be implemented after the expiration “of both. -year limit.

The samples, if stored properly, could contain crucial signs of the first human-made antibodies to the disease, experts said.

Liang said in July that although the first reported case was in Wuhan on December 8, “our research and previous related research documents from Chinese scientists fully suggest… December 8 is probably not the main case. There could be other cases that have occurred. before.”

Dr William Schaffner, of the Division of Infectious Diseases in the Department of Medicine at Vanderbilt University, said the samples presented a “fascinating opportunity. You’d like to go back to find out exactly which months this virus began to leave behind. fingerprints in the human population in China. “

China to test thousands of blood samples from Wuhan in Covid-19 probe

The samples could even show who was infected for the first time, where, their age and occupation, Miller added.

“It is common practice to anonymize samples,” she said. “So you can narrow it down to basic demographics, age, gender of the neighborhood they lived in. All of that data will be available.”

Schaffner suggested that the samples could be brought to Geneva, or another neutral destination, to allow WHO experts to participate in the testing.

He said two possible problems with the samples could be “the integrity of the blood samples – making sure they had not been created recently”, but also to what extent the blood donors were representative of the population as a whole. Miller said many samples would most likely have been taken from healthy individuals “so they will represent asymptomatic cases. And as we have learned during the pandemic, asymptomatic cases fuel the pandemic.”

Huang said it was not clear to what extent “the outside world would trust the results to be credible or convincing,” and the tests provided an opportunity for China to “tell the world that it is seriously considering to depoliticize the investigation of the origins “.

The Biden administration carried out a 90-day review of information on the origin of the virus, but an unclassified report had officials still considering both natural transmission from animal to human and a laboratory leak. as plausible theories, but unable to determine which was more likely. .

President Joe Biden, receiving a classified version of the report, said: “Critical information about the origins of this pandemic exists in the People’s Republic of China, but from the start Chinese government officials have worked to prevent international investigators and members of the global public health community to access them.

China insisted it had been transparent and useful to the WHO’s investigation, and in its most recent statement on the theory that the virus had leaked from a laboratory, pointed out claims not evidence concerning Fort Detrick, the American laboratory in Maryland, and the need to examine its recent past.