I've not seen inter cellular Uronema cross between fish from different importation groups. What I mean is; let's say I bring in a group of 25 green chromis. I may see Uronema lesions in a percentage of them, but not in other fish from other shipments in the same system with them. Can I say for certain that the Uronema isn't transmitting between green chromis? No, but by not seeing it transmit from the green chromis onto other fish in the system, I presume not.
In case you haven't seen it, here is a link to my Uronema article:
Red Band Syndrome in Marine Fishes: Caused by the Protozoan; Uronema sp. Jay Hemdal Introduction: This moderately common disease of certain species of marine fish is so often misdiagnosed that most aquarists apply incorrect treatment methods...
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