A newly public U.S. intelligence report is raising new questions about the idea that the novel coronavirus, SARS-CoV-2, escaped from a lab.
According to the Wall Street Journal, the report states that three employees of the Wuhan Institute of Virology sought hospital care in November 2019, approximately when SARS-CoV-2 is thought to have started circulating in the Chinese city. The Institute works with coronaviruses found in animal populations.
However, it's unclear how sick the researchers were or what their symptoms were. In the Chinese medical system, it's common to seek entry-level medical care directly from hospitals rather than outpatient clinics, according to the Wall Street Journal, and there is no information on whether the employees were admitted for inpatient care or seen as outpatients.
The new information is likely to increase pressure for more investigations into the origin of the novel coronavirus. Previous work on the genetics of the virus has shown no signs of human tampering: The virus resembles coronaviruses known to circulate in bats or pangolins, with a mutation in the virus's spike protein that enables the virus to more easily invade human cells, helping to enable person-to-person spread. But this mutation is not what computer simulations predicted would have made the virus more transmissible. Instead, this genetic fingerprint makes the most likely reason for the pandemic a lucky break for the virus: Random mutation appears to have stumbled upon a sequence that allowed the virus to take off in a new host in a classic case of natural selection, according to a March 2020 paper in the journal Nature Medicine (opens in new tab).
"This analysis of coronavirus genome sequences from patients and from various animals suggests that the virus likely arose in an animal host and then may have undergone further changes once it transmitted and circulated in people," Adam Lauring, an associate professor of microbiology, immunology and infectious diseases at the University of Michigan Medical School who was not involved in that research, told Live Science in April 2020.
As the rise of new SARS-CoV-2 variants shows, the virus mutates regularly, and some of those mutations are associated with changes in how effectively it transmits.
The earliest reported outbreak of the virus occurred at the Huanan Wholesale Seafood Market in Wuhan. Initially, some speculated that the virus had jumped from animal to human at the market, because live animals were housed and sold there. However, it soon became clear that the wet market may not have been the original site of that leap: There were early cases of COVID-19 in the city not connected to shoppers at that market, and there have not been any SARS-CoV-2 sequences found in animals from the market. Instead, it seems that the market was simply the site of the first recorded super-spreader event. The World Health Organization (WHO) has said that the most likely origin of the virus was that it spread from bats to another, unknown animal, and then from there to humans.
The finding that SARS-CoV-2's genome was unlikely to have been genetically engineered does not preclude the hypothesis that the virus escaped from a lab. It could have been a naturally occurring virus that was being studied there that inadvertently infected humans. Chinese authorities and researchers at the Wuhan facility deny that the virus was present in the lab. Lists of the viruses studied at the lab, released by the facility, show no close cousins to SARS-CoV-2.
The Wuhan Institute of Virology is China's first biosafety level 4 facility, meaning it's designed for research on potentially dangerous pathogens and that researchers take precautions against aerosol transmission. In April 2020, reporters obtained cables written by U.S. diplomats in 2018 asking for more support for the facility. The cables warned that the lab lacked adequate staff and training needed to safely conduct its potentially dangerous research on coronaviruses. The laboratory has not shared its data or lab records in the wake of the pandemic, the Wall Street Journal reported. Nor has the Chinese government always been forthcoming about data from the first days of the pandemic. For example, officials have declined to make raw data about seasonal illness in the country in fall 2019 available.
There has been little evidence to directly tie the Wuhan lab to SARS-CoV-2, however. The new intelligence on the three sick staffers comes from an unknown source. One person told the Wall Street Journal that the source was an "international partner" and needed collaboration. Another said the intelligence was of "exquisite quality." A State Department fact sheet released at the end of the Trump administration had already called attention to reports that lab members fell sick in fall 2019 with "with symptoms consistent with both COVID-19 and common seasonal illness," but the new report claims to add more specificity.
The Biden Administration declined to comment on the new information beyond generalities, according to the Wall Street Journal. "We continue to have serious questions about the earliest days of the COVID-19 pandemic, including its origins within the People's Republic of China," a spokesperson for the National Security Council told the newspaper.
On March 30, WHO called for continued research into the virus' origins. "As far as WHO is concerned, all hypotheses remain on the table," director-general Dr. Tedros Adhanom Ghebreyesus said in a statement.
Originally published on Live Science.