An aerial view shows a laboratory at the Wuhan Institute of Virology in central China's Hubei province. Photo: AFP

While the source of the Covid-19 pandemic has not been determined completely, there has been intense interest in this subject. Apparently the intelligence community is not discounting a range of possible transmission vectors, including contact between humans and animals, but officials are also seriously pursuing the possibility that a natural sample of the virus escaped a laboratory.

Most experts believe the outbreak began when animals passed the virus to humans in China, specifically in or near a market in the city of Wuhan where live animals were sold. However, the possibility that the virus leaked during a lab accident is being seriously considered by the US and UK governments.

A UK parliamentary committee few weeks ago accused the Chinese government of spreading disinformation about the origins of the virus. Britain is still not dismissing the notion that the pandemic might have been touched off by an accident at a research facility rather than by an infection from a live-animal market.

Both the US and the UK suspect that Chinese officials failed to ensure inspectors adhered to the United Nations’ Biological Weapons Convention, including by not providing information about research on numerous toxins with potential dual-use application.

While Chinese officials were quick to link the origin of the disease to infected animals at a Wuhan wet market, which was formally closed on January 1, scientists have not traced the initial exposure back to any specific animals. Therefore, an alternative possibility remains that a natural virus sample being studied at a research laboratory in Wuhan infected a researcher who then spread it in the community, or that it escaped via hazardous waste or a lab animal. 

There are reasons to be wary of that theory. It could serve as a propaganda tool for politicians who want to ramp up tensions with China, and many scientists still argue that a natural outbreak is the most likely possibility, dismissing any alternative theory. But finding the source of the outbreak could also be vital in understanding how it spread and how to prevent the next potential pandemic.

One reason for the suspicion is the lack of information coming from China. Beijing’s initial denials of involvement, and the decision immediately to identify the Wuhan wet market as the source, have raised eyebrows among some intelligence officials.

In fact, some of the very first cases of Covid-19 were not linked to the market, and there are a number of important research institutions in Wuhan where infectious diseases are studied. They include the Wuhan National Biosafety Lab, the first publicly acknowledged laboratory with the highest biosafety standards; the Wuhan branch of the Chinese Center for Disease Control and Prevention; and the Wuhan Institute of Virology, home to one of the world’s top research groups on bat coronaviruses, where scientists have studied thousands of samples.

The Wuhan Institute of Virology, which collaborates with researchers and institutions around the world, including the US National Institutes of Health, is a key site for the Global Virome Project, an international initiative focused on preventing pandemics by researching the DNA and RNA of viruses in animals that could potentially infect humans. While that group does not typically work with intact virus samples, it is possible that researchers could have collected a virus sample from a bat and been researching it within the lab.

Not all scientists agree with this possibility, and it seems a valid argument that the new virus, SARS-CoV-2, emerged too recently to have been identified, isolated from other virus samples, cultured and then accidentally released from a lab. Because there is so much variety in types of coronavirus in bats and other species, virus specimens are massively under-sampled, making it less likely Chinese researchers discovered this specific strain.

However, even Chinese researchers initially pointed to the possibility of a lab accident in a study published in February on ResearchGate. Botao Xiao and Lei Xiao of Guangzhou’s South China University of Technology wrote, “The killer coronavirus probably originated from a laboratory in Wuhan,” although they also raised the possibility of natural transmission. Botao Xiao later withdrew the paper, telling The Wall Street Journal he did not have evidence for his theories.

Now whether the virus escaped from a lab or not, the upside from this is that the current pandemic will spur higher lab safety standards worldwide. Certainly standards are not clear enough, are not uniformly practiced, and are not keeping up with advances in biological technologies.

Clinically speaking, virus collection, culturing, isolation, or animal infection at BSL-2 (moderate biosafety level) with a virus having the transmission characteristics of SARS-CoV-2 could pose substantial risk of infection of a lab worker, and from the lab worker, the public. However, while the available evidence provides a basis to rule out a lab construct, it does not rule out a lab accident. In other words, while the virus is not believed to have been created in a lab, it could have been studied in one and released by accident.

Without a credible whistleblower or verified primary communication intercept, it may not be possible to prove the origins of Covid-19 with certainty.

Dr Fawad Kaiser is a professor, Fellowship Diplomate of the American Board of Psychotherapists, and a member of the International Association of Forensic Criminologists. He is currently a consultant forensic psychiatrist in the UK.