Question About Spreading Virus

[Andrew]

The underlying problem I have with blanket statements that CMV and ORSV are mechanically transmitted rather than transmitted by pests is that it ignores the fact that these viruses have evolved in the absence of human manipulation. Tissue/sap contact isn't an effective mode of viral transmission if the host doesn't move!

I guess pollinator transmission is possible although I would expect a pollinator transmitted virus to be much more prevalent in the wild than these viruses apparently are; given that infection rates are supposedly very low in nature judging by the unlikely 'orchid supposition' that orchid viruses don't occur in the wild. After all, HIV and herpes certainly don't have a problem spreading through the human population.

Granted pest transmission rates may be very low compared to mechanical trasmission but can pest transmission be completely ruled out?