[nnq]

Hmm... ADE shouldn't happen with natural immunity post-infection since the body tends to produce a cocktail of different antibodies and either some or the combo would have some virus neutralizing effects. But it's known to happen in-vitro and with vaccine generated antibodies (always less diverse than the ones generated naturally).

Natural-ADE shouldn't thwart development of a live/innactivated-virus vaccine though. But would immensely slow the dev of RNA or protein ones since you'd have to test through a lot of candidate variants until you find one that is not ADE-inducing...

Otoh, a population of naturally-immune survivors is a living library of antibody cocktails that are know to work. If I were more conspiracy-theory inclined, I'd say the UK gov. has knowledge along these lines and they are willing to sacrifice some of the gen. pop. knowing that (a) it will take a looong time to a good vaccine, so better for the economy if they get natural immunity faster than everyone else, also lots of arbitrage opportunities on international markets once they're first to recover, and (b) they bet their "living library" of good antibodies will maybe make them a leading producer of safe vaccines.

Now, if this COVID bugger does ADE with naturally induced immunity... that's BAAAD! Natural evolution would have no reason to optimize in that direction, and genetic lottery is probably not likely to produce this. You get the conclusion and geopolitical consequences... it's something something about that doomsday-clock striking a certain hour...

DISCLAIMER: I'm not an expert on the topic, or any other topic in general. Just another expert-generalist currently doing mostly software thinggies but having some old and rusty biomedsci background...