We also have more genes overall, so in absolute terms the difference between us and chimpanzees or fruit flies is pretty large compared to the differences betwe

We also have more genes overall, so in absolute terms the difference between us and chimpanzees or fruit flies is pretty large compared to the differences between those two viruses. Also we basically have all the ingredients to procreate ourselves (we only need to team up with someone from the other sex), while viruses partly rely on the protein synthesis machinery of the host. So viruses can do away with conserved proteins they will find in most of their hosts, we can't.