I’m going to presume for a moment that as a fan of classic Trek that you’re also likely a fan of Firefly and — by extension — the movie Serenity. Specifically, Serenity. And even more specifically that moment when Mal reveals he knows what an albatross is.
As I recall the albatross was a ship’s good luck until some idiot killed it. Yes, I’ve read a poem, try not to faint.
Malcolm Reynolds as portrayed by Nathan Fillion in the film Serenity.
Why does this matter? Because Bones is “on trial” as having caused a plague 20 years earlier and those holding him for trial are already convinced of his guilt and that he’ll be granted capital punishment in accordance with their planet’s laws.
But Kirk takes matters into his own hands — like you do, when you’re Kirk — and finds a witness for Bones’ defence and remnants of the plague and then catches plague and then Spock has to go on one-man jailbreak to free McCoy to cure/immunize everyone.
And based on the witness having been immunized once twenty years ago and then needing to be immunized again, we can see that the immunity provided is temporary like our annual flu shots and not permanent like the shot we get for mumps.
And as much as I’d love to spend more of this pandemic thinking about epidemiology, I’m really just happy for an excuse to make a Serenity reference and also re-read The Rime of the Ancient Mariner … or at least read about it given that it is in fact the longest (major) poem by Samuel Taylor Coleridge. Because this whole episode is about stopping Bones from the fate of the albatross even as he sits in prison feeling the weight of the bird (some unknown tragic mistake he might have made) hanging around his neck).
That corpse you carry everywhere and keeps you pris'ner in this place, it is a thought-form without care but for what's writ upon your face. There is no jailer, key or crime, but your forgetting all that time and pouring in its place your fear most grave and loathsome, without peer. Open your eyes! Open your eyes! How precious high you lift all life with your sweet vow to end all strife! Look to your work for clearer skies, the siren call of others' need is all your brave knows how to heed.