It’s a rumour that just won’t go away.
Since the start of the pandemic, accusations that the SARS-CoV-2 virus responsible for Covid-19 was designed to be a bioweapon have abounded.
The fact that an advanced virology laboratory is present in Wuhan, where the global pandemic began, has only fed ideas that the Chinese government purposefully created the virus as a bioweapon. On the other hand, some commentators in China have claimed that they were the victim of an American attack.
But behind all these claims and allegations, is there any truth to the idea that the novel coronavirus was genetically engineered to be a bioweapon and was released either deliberately or accidentally?
In short, no; and for various scientific and practical reasons. Although biological warfare is certainly a reality, historically it has not been the harbinger of Armageddon that science-fiction films portray it to be. Many bioweapons produced during the Cold War were actually targeted at agricultural crops and livestock, thereby damaging an enemy nation’s food supply and economy. In fact, an ideal bioweapon would not be highly communicable between humans, as this reduces the risk of uncontrolled spreading of the disease beyond the target area.
In the few documented instances where states worked on using highly infectious diseases as bioweapons, research was focused on those diseases for which vaccines or drugs were known, such as smallpox or plague. This meant that if the bioweapon unintentionally spread outside the target area, it could be brought under control relatively quickly.
With all this in mind, the coronavirus responsible for the current pandemic just doesn’t seem to have the qualities of a good bioweapon. It is highly communicable, results in a long and unpredictable incubation period, and is difficult to treat, meaning it can not be used in a targeted attack and would very likely spread back to the nation where it was developed. Furthermore, it disproportionately targets the elderly and vulnerable, but does not have as drastic an effect on those members of the population who are more likely to be economic drivers or members of military forces.
So, we know that the novel coronavirus does not have any of the qualities that are typically characteristic of good bioweapons. But is there good scientific evidence that rules out a man-made origin?
The answer is yes: Kristian Andersen, a professor of immunology and microbiology at the Scripps Research Institute, assembled a team of virologists, evolutionary biologists, and geneticists to study the genetic composition of the virus and look for any tell-tale signs of human interference or genetic manipulation. They also compared the genetic code of the SARS-CoV-2 virus to that of seven other coronaviruses also known to infect humans.
Their results, published in the respected and peer-reviewed scientific journal Nature Medicine, showed that SARS-CoV-2 is somewhat genetically distinct from the seven other coronaviruses, and is more closely related to viruses that infect bats and pangolins, which do not cause any illnesses in humans. According to the researchers at Scripps, this disfavours the idea that the virus was man-made, since “if someone were seeking to engineer a new coronavirus as a pathogen, they would have constructed it from the backbone of a virus known to cause illness.”
[attach id=871136 size="large" align="left" type="image"]A man walks past a mural of two healthcare workers in Guerrero state, Mexico. Photo: AFP [/attach]
The research team also examined the genetic code for the spike proteins that protrude from the surface of the virus. The novel coronavirus uses these spike proteins to hook on to a protein receptor called ACE2 on the walls of human cells and then enter them. Their analysis showed that the SARS-CoV-2 virus binds to these receptors more tightly than other coronaviruses which infect humans, but similarly to related viruses known to infect pangolins. Furthermore, the structure of the spikes on SARS-CoV-2 is different from those on other human coronaviruses, as they contain special sites at which sugar molecules may attach and create a shield which protects the virus from an immune response.
These results are compelling evidence that SARS-CoV-2 is not man-made. The genetic and structural similarity of the virus to those observed in pangolins and bats points towards a natural spill-over incident from animals to humans. The fact that the spike proteins on the surface of the virus allow for the formation of a shield made from sugar molecules to protect against the body’s immune system also indicates a natural origin. Laboratory-based tissue cultures have no immune systems, and so it is highly unlikely that such an adaptation would arise from genetically manipulating the virus in a laboratory setting.
The scientific community seems to have found consensus in the fact that the SARS-CoV-2 virus is not a product of nefarious governments or sinister genetic experiments gone awry. While there are certainly many questions that remain to be answered regarding the exact origin of the coronavirus and how it crossed the species barrier, scientists are confident that the origin was a natural one.
Duncan V. Mifsud is a doctoral candidate at the Centre for Astrophysics and Planetary Science at the University of Kent and a Fellow of the Royal Astronomical Society. His research is currently focused on radiochemical changes to the surfaces of the Galilean moons of Jupiter.
Benji Fenech-Salerno is a doctoral candidate at the Department of Chemistry, Imperial College London. His research is currently focused on wearable nanoelectronics used in disease detection.