New genetic evidence from the Huanan Seafood Wholesale Market in Wuhan, China, where COVID-19 cases first emerged in late 2019, supports the theory that the virus originated from animals.
The WHO has criticized China for hiding this crucial information, and GISAID has faced scrutiny for its role in controlling access to the data.
The findings were presented to an advisory group convened by the World Health Organization (WHO) earlier this month.
Florence Débarre, an evolutionary biologist at the French National Center for Scientific Research, discovered genetic sequences of the virus uploaded by Chinese researchers to a public genomic database called GISAID.
These sequences were later removed, but not before other researchers analyzed them.
The samples contained viral RNA from the market in early 2020 and also contained genetic material from raccoon dogs and other animals.
Raccoon Dogs: A Possible Link
The presence of genetic material from raccoon dogs, a foxlike type of canid, in the same areas of the market where SARS-CoV-2 was found suggests that these animals may have been infected with the virus (possibly by other animals) and could have been the first to spread the virus to humans.
While this new evidence does not directly prove that SARS-CoV-2 jumped into humans from infected raccoon dogs, it adds to a growing body of evidence supporting a spillover from animals.
Weighing the Evidence
In an interview with Scientific American, Joel Wertheim, an evolutionary biologist at the University of California, San Diego, explained that the new discovery is consistent with a natural zoonotic spillover, an animal disease jumping into humans.
Wertheim acknowledged that the genetic material’s co-occurrence does not directly indicate infection in raccoon dogs or other mammals, but it does provide forensic evidence that these potential host animals were present at the market.
The new evidence also raises questions about lab-leak hypotheses, which Wertheim believes are mutually incompatible with each other.
No suspicious signs of lab manipulation were found in the viral genome.
Wertheim argued that the most charitable explanation for the lab-leak theory is unlikely, given the lack of evidence and the difficulty in tracing the virus back to any lab workers.
Data Access Controversy
The recent findings have sparked a battle for access to genetic sequences.
Chinese researchers initially uploaded the raw sequences to GISAID, but they were taken offline after international experts discovered the data and alerted Chinese researchers.
The WHO has criticized China for hiding this crucial information, and GISAID has faced scrutiny for its role in controlling access to the data.
The Importance of Biosecurity
Although the evidence points to a natural zoonotic origin for COVID-19, the discussion surrounding biosecurity and lab safety remains crucial.
Wertheim emphasized the importance of separating these two issues, as the circumstances of the virus’s origin should not be conflated with concerns about lab security.
Future Research
The international team of scientists continues to investigate the new genetic evidence, hoping to glean more information from the market samples.
They are particularly interested in sequences from stalls without SARS-CoV-2 and any additional genetic data from the market that has not yet been made available.
Sharing these data with the broader scientific community is essential to furthering our understanding of the virus’s origins.
