I find a large number of Camponotus here are infected with parasites, I usually lose 25-50% depending on the day. I'm not complaining, as there are so many Camponotus pennsylvanicus in my area, it helps keep their population down. It's only disappointing if the infected queen was a species I wanted to keep.
Years ago my Dad used to work for a biomedical company that was trying to find environmentally friendly ways to destroy pest species like Camponotus, termites, and cockroaches using existing things from nature. I went there a couple of times, and they huge colonies of all of them all over, both in the lab and an external warehouse for propagation. They used several techniques, and I remember one was using mites to wipe out Camponotus. Worked really well, but unfortunately company didn't make it. Wish I could remember more, but was a long time ago.