Well, let's focus on Step One... identifying the immune fish. I think what you described could be a survivor-carrier.
Yes, Sakai and his ilk are ready to experiment... but with KHV? If they did, I think it would be at separate facilities and in secret. ...OK, I'll give you that one.
Hmmmm. Short memories and over-long memories and imagined memories. I was over at a smiley-face board. I'd not rely on accurate memories.
