Scientist group: Evidence shows coronavirus evolved in nature

The virus that led to the COVID-19 pandemic evolved in nature, while suggestions of a laboratory-leak source "remain without scientifically validated evidence", a group of international scientists have written in The Lancet medical journal.

In a letter published on Monday, 24 physicians, veterinarians, epidemiologists, virologists, biologists, ecologists and public health experts from around the world continued to dismiss the lab-leak idea, as more recent, peer-reviewed studies strongly suggest that COVID-19 has a natural origin.

In February 2020, at the beginning of the pandemic, the same team of scientists wrote in a letter, also on The Lancet, saying: "We stand together to strongly condemn conspiracy theories suggesting that COVID-19 does not have a natural origin."

"Recently, many of us have individually received inquiries asking whether we still support what we said in early 2020," they wrote in a new letter titled "Science, not speculation, is essential to determine how SARS-CoV-2 reached humans".

"The answer is clear: we reaffirm our expression of solidarity with those in China who confronted the outbreak then, and the many health professionals around the world who have since worked to exhaustion, and at personal risk, in the relentless and continuing battle against this virus. Our respect and gratitude have only grown with time," the authors wrote.

The authors said their original letter was also intended to express their working view that SARS-CoV-2 "most likely" originated in nature and not in a laboratory.

This view was based on early genetic analysis of the new virus and "well-established evidence" from previous emerging infectious diseases, including the coronaviruses that cause the common cold as well as the original SARS-CoV and MERS-CoV, they noted.

SARS-CoV-2 stands for severe acute respiratory syndrome coronavirus 2, the virus that causes COVID-19 disease, while MERS is short for Middle East Respiratory Syndrome, another viral respiratory illness.

As of Tuesday, the world has reported more than 183.9 million confirmed coronavirus cases, with the COVID-19 death toll nearing 4 million, according to the World Health Organization statistics.

"We believe the strongest clue from new, credible, and peer-reviewed evidence in the scientific literature is that the virus evolved in nature, while suggestions of a laboratory-leak source of the pandemic remain without scientifically validated evidence that directly supports it in peer-reviewed scientific journals," the new letter stated.

In March, the WHO released the origin-tracing study report of the China-WHO joint mission, drawing a conclusion that lab leak is "extremely unlikely".

In late May, US President Joe Biden called for a US-based probe into the origins of COVID-19. The administration gave US intelligence agencies 90 days to report whether the virus originated from an animal source or from a laboratory accident.

Almost a month later, the Biden administration officials cautioned that the 90-day review may not produce a "definitive" explanation as intelligence agencies take on the challenge of unraveling the global pandemic, The Wall Street Journal reported on June 27.

Beijing has strongly opposed the politicization of COVID-19 origin tracing, saying that it is a scientific issue, on which China has always maintained an open and transparent attitude.

The Lancet letter authors also said allegations and conjecture are of no help, as they do not facilitate access to information and objective assessment of the pathway from a bat virus to a human pathogen that might help to prevent a future pandemic.

"Recrimination has not, and will not, encourage international cooperation and collaboration," they noted.

"It is time to turn down the heat of the rhetoric and turn up the light of scientific inquiry if we are to be better prepared to stem the next pandemic, whenever it comes and wherever it begins," they wrote.

The authors are scientists from universities and institutes in countries including the US, UK, Germany, Spain, Italy, Australia, Malaysia, and China's Hong Kong Special Administrative Region.