Forums of the Megaverse®

One of the rifters(the one about the Lone Star Cavalry #12 I think) had some computer viruses that could infect some bugs.

The latest Rifter (#26) contained my article called fleas. It's a little bit of what you were looking for. Basically the small fleas latch to the bugs to drink from them in either energy form or physical form. The encounter can cause sickness or even mutation. Since the bugs don't tolerate any mutated or sick in their culture any such bug will be destroyed by it's own kind. The fleas travel with the bugs in energy form so they can go back to spread them to the other bugs in their strongholds.
It has rules for breeding and spreading the fleas, including dangers to humans and organitech. There are also common traps to spread the fleas to the bugs in different ways.

They're not something from earth but from the bug homeworld.

So that's the closest thing I can think of what you described.

Zor's material is very useful and well thought out. Another weakness that I had played with in my timeline that was on NMI's board was that the Bugs of rival hives would fight each other over resources. The location that I had used to demonstrate that was Sacramento California.