@Glassmaker - I had kind of the same question, but I think Karl has answered it in some of his other Tickers. A virus tends to mutate toward perhaps more contagious strains, and away from more virulent / dangerous strains, as a quick acting "death sentence" virus cannot spread rapidly and would basically kill itself off.

So.. that ADE targeting bioweapon virus would kill off a very large percentage of the covid vaccinated people, and later mutations of that same virus would have little effect on non previously covid vaccinated people.