COVID-19 ORIGINSCOVID-19 Origins Linked to Wildlife Sales at Chinese Market; Other Scenarios Extremely Unlikely: Studies
Analyses based on locations and viral sequencing of early cases indicate the COVID-19 pandemic started in Wuhan’s Huanan Seafood Wholesale Market, with two separate jumps from animals to humans.
One of the most intriguing, and politically fraught, questions about COVID-19 is whether the disease spilled over naturally from animals to humans, or whether it was the result of a lab accident.
Some even speculated that the virus was part of a Chinese bioweapon research.
An international team of researchers has now shown that live animals sold at the Huanan Seafood Wholesale Market in Wuhan, China, were the likely source of the COVID-19 pandemic that has claimed 6.4 million lives since it began nearly three years ago.
Led by University of Arizona virus evolution expert Michael Worobey, researchers traced the start of the pandemic to the market in Wuhan, where foxes, raccoon dogs and other live mammals susceptible to the virus were sold immediately before the pandemic began. Their findings were published Tuesday in two papers in the journal Science, after being previously released in preprint versions in February.
The publications, which have since gone through peer review and include additional analyses and conclusions, virtually eliminate alternative scenarios that have been suggested as origins of the pandemic. Moreover, the authors conclude that the first spread to humans from animals likely occurred in two separate transmission events in the Huanan market in late November 2019.
One study scrutinized the locations of the first known COVID-19 cases, as well as swab samples taken from surfaces at various locations at the market. The other study focused on genomic sequences of SARS-CoV-2 from samples collected from COVID-19 patients during the first weeks of the pandemic in China.
The first paper, led by Worobey and Kristian Andersen at Scripps Research in San Diego, California, examined the geographic pattern of COVID-19 cases in the first month of the outbreak, December 2019. The researchers were able to determine the locations of almost all of the 174 COVID-19 cases identified by the World Health Organization that month, 155 of which were in Wuhan.