This is a recent discussion on This Week in Virology: https://youtu.be/IxwrDSYrhjU https://youtu.be/IxwrDSYrhjU. The main reasons why virologists think the ide

This is a recent discussion on This Week in Virology: https://youtu.be/IxwrDSYrhjU https://youtu.be/IxwrDSYrhjU. The main reasons why virologists think the idea of a lab leak is nonsense: * Nothing in the genome of SARS-CoV-2 is particularly surprising. All the elements of the virus (including the furin cleavage site) are commonly found in other coronaviruses. * Every novel virus in history has been the result of spillover from animals. Just in the last 20 years alone, two novel coronaviruses have spilled over into humans: SARS and MERS. SARS-related coronaviruses are circulating in bat and other animal populations throughout China and Southeast Asia, and millions of people come into regular contact with these animal populations. These millions of people are not trained researchers wearing protective gear and undergoing regular testing for infection. Literally millions of people are constantly exposed at much higher levels than researchers. * There is not a single shred of evidence that the Wuhan Institute of Virology had SARS-CoV-2 before the pandemic. None. On the other hand, there's good evidence that they didn't have it. They publish the genomes of viruses they find (such as the now-famous RaTG13, which they published in 2016), and SARS-CoV-2 is not among them. * The Wuhan Institute of Virology has only ever isolated three SARS-related coronaviruses, and it has published extensively on them. All three of them are only distantly related to SARS-CoV-2. All the gain-of-function conspiracy theories require SARS-CoV-2 to have been secretly isolated in a lab, which is a very difficult and time-consuming task, without anyone being informed, without anything being published, and without any of the many people who would know about this (very likely including foreign scientists) spilling the beans. * The Wuhan Institute of Virology, just like all other well-run high-security labs, regularly tests its workers for signs of infection. If lab workers had been infected, they would be seropositive. The lab-leak conspiracy theory requires the lab to be lying about its testing results.