At the very end of 2019, a new disease began to emerge in humans: COVID-19. Originally described as a set of pneumonia-like symptoms with a hitherto unseen cause, a set of alarming facts soon came to light. A novel virus — now known to be SARS-CoV-2 — had begun infecting humans, with the first major outbreak stemming from a wet market in Wuhan: the largest city by far in the Chinese province of Hubei. The next pandemic, just as virologists and disease ecologists had been predicting for years, emerged from the continued encroachment of human civilization on territory previously inhabited solely by wild animals. Human-animal contact, responsible for pandemics ranging from SARS to MERS to Ebola to HIV, was almost certainly the culprit in bringing this novel coronavirus into the human population as well.
But this explanation for SARS-CoV-2, claiming that it had a zoonotic origin, has been disputed by some, despite the lack of any publicly available scientific evidence to the contrary. Instead, according to recent claims, the virus may not have originated and spread from the wild, but could have escaped, in a lab leak, from the Wuhan Institute of Virology. From the point of view of the virus’s genome, there’s no way to rule such a possibility out, so long as the virus was never characterized or reported in the lab before its escape. But is this lab leak hypothesis a legitimate scientific theory, on equal or even superior footing with the zoonotic origin theory? Or is it a conspiracy theory, without the scientific evidence to back up these wild assertions? Let’s take a comprehensive look to try and unpack everything that’s been going on.