In general this line of argument is questioning how we can know that a particular virus causes a particular disease. It ignores decades of technological improvements developed toward actual viral bulkup, purification, and infection.
Is it easy to know that a particular virus causes a particular disease? Not always, particularly if the disease syndrome is complex. Is it possible to link particular viruses to particular diseases? Definitely. For the more straightforward diseases it's even relatively straightforward to show that a particular virus causes that particular disease, with enough work.
> For the more straightforward diseases it's even relatively straightforward to show that a particular virus causes that particular disease, with enough work.
I'd be really interested what this work would look like. Koch's Postulates have always made logical sense to me and I've never understood why they where abandoned for virology. How can we prove a high likelihood of causation when at best we only have data of hosts that already showed signs of disease?
Aside - this thread seems to have gone down a rabbit hole where many are assuming I'm claiming viruses don't exist or don't cause disease. I get that viruses have been made a political topic these days, but I'm only raising that as far as I'm aware viruses have never been isolated in the same way as bacteria or fungi. We've never, again as far as I'm aware, isolated a virus from a sick person, exposed a healthy person to it, and seen the same disease symptoms show up with the virus now present in their system.
One could point to vaccines for this proof, but even those include other adjuvants that are present specifically to inflame the host and help promote a stronger immune response. I'm not claiming that including those adjuvants is a problem as far as the vaccine goes, only that it doesn't fit the definition of introducing an isolated virus.
Have we found plenty of evidence that a specific virus is present in a host after symptoms are shown? Absolutely. But have we ever successfully checked the box on Koch's Postulates with a virus? Not that I know of.
anonymouskimmer|2 years ago
Is it easy to know that a particular virus causes a particular disease? Not always, particularly if the disease syndrome is complex. Is it possible to link particular viruses to particular diseases? Definitely. For the more straightforward diseases it's even relatively straightforward to show that a particular virus causes that particular disease, with enough work.
_heimdall|2 years ago
I'd be really interested what this work would look like. Koch's Postulates have always made logical sense to me and I've never understood why they where abandoned for virology. How can we prove a high likelihood of causation when at best we only have data of hosts that already showed signs of disease?
Aside - this thread seems to have gone down a rabbit hole where many are assuming I'm claiming viruses don't exist or don't cause disease. I get that viruses have been made a political topic these days, but I'm only raising that as far as I'm aware viruses have never been isolated in the same way as bacteria or fungi. We've never, again as far as I'm aware, isolated a virus from a sick person, exposed a healthy person to it, and seen the same disease symptoms show up with the virus now present in their system.
One could point to vaccines for this proof, but even those include other adjuvants that are present specifically to inflame the host and help promote a stronger immune response. I'm not claiming that including those adjuvants is a problem as far as the vaccine goes, only that it doesn't fit the definition of introducing an isolated virus.
Have we found plenty of evidence that a specific virus is present in a host after symptoms are shown? Absolutely. But have we ever successfully checked the box on Koch's Postulates with a virus? Not that I know of.