I wonder if orchids (plants) are similar and everyone of them are full of bacteria & virus, and like human when the host is weak , stressed or out of balance, the good bacteria & virus are overwhelmed by the bad ones , and symptom shows .
When I look at leaves under a microscope, I am always surprised at the damage and fungal hyphae penetrating the outer layers. It is a constant battle between plants and the bacteria and fungi trying to consume them. When the damage becomes too great, the tissue dies and the area is isolated. I would assume virus and bacteria are moving throughout the plant. Probably doesn't matter until something more virulent comes along.Me too. Will be interesting to see if any studies have been done on plants - by using electron microscopes of a suitable kind ---- to see if orchids just have viruses in them - dormant or otherwise.