According to Dr Andrew Kaufman's conspiracy theory, the novel coronavirus (SARS-Cov-2) is in fact an exosome. After seeing this pseudoscientific hypothesis, I realized that many facts are incorrect. In fact, I would like to debunk with facts several statements I've found over and over again in social media.
Controls are used in virus culture
SARS-CoV-2 is usually cultured using the VeroE6 cell line and, despite Kaufman's claims, a control is usually used. For example, that was done with the first COVID19 patient in Australia:
Here you can see a viral cytopathic effects produced in Vero/hSLAM cells by a sample containing the virus. The bottom line are uninfected cell lines.
SARS-CoV-2 is not an exosome only produced by Vero cells
Other cell lines are used to culture the virus and they give the same result, like Huh7, or human airway epithelial cells, but there are cell lines which have more advantages in viral culture than other.
SARS-CoV-2 cannot be an exosome
Our cells do produce exosomes, but exosomes cannot contain genetic information not contained in our genome. SARS-Cov-2 contains unique information which characterizes it, its genome has been completely sequenced and tracing mutations is a useful way to trace the virus around the world.
Exosomes of infected cells, can, in fact, contain viral RNA. This is just if, and only if, the cell is infected by SARS-CoV-2.
SARS-CoV-2 has never been isolated
That completely false. As I showed above, it has been fully sequenced. You also can see it using electron microscopes:
But Koch's postulates have never been applied to the novel coronavirus!
Take a look at Koch's postulates. It's completely unethical to induce a disease in a human being to prove Koch's postulates. Currently, we have lots of new techniques anyway. In the lab, the virus not only infects cell lines, animals are also used as a tool to evaluate new treatments and to understand the virus better.