I suspect, can't prove, that probably many viruses that are cytolytic
in vitro may not be in vivo. Virtually all the hepatitis viruses are currently
thought to be non-cytopathic to cells, disease resulting from the cellular
immune response aimed at killing virus-infected cells.
Another mechanism of cell killing by viruses may well involve a
triggering apoptosis- programmed cell death. I think this is an area of