My answer is based off the nature of what a 'vaccine' is. Nanoplasmosis is more in the nature of an antibiotic - specifically, a counter-infestation. Use nanoplasmosis to take care of the active CFD vector (whatever alterations have been made are gonna be permanent anyhow), then cure the nanoplasmosis. It should be effective, yes - but that doesn't make it a vaccine.
Well, perhaps calling it a vaccine was a mistake on my part. What I meant was: "something that would fight off the nanites"
Agreed re: vaccine* but I don't see it as an antibiotic parallel, I think it's the equivalent of pre-antibiotic treatment of syphilis with malaria.
The idea was to give malaria (which had a known cure - quinine) to those with syphilis (which didn't). The high fevers of malaria wiped out the syphilis and then quinine was used to purge the malaria.
Huh, didn't know that. Still, even with medication, isn't malaria more dangerous than syphilis (read: kills faster)?
Back to the subject of CFD vs nanoplasmosis, personally, I would rather risk toxoplasmosis-like symptoms than a full personality override. Especially in the world of Shadowrun, with all of it's medical breakthroughs.
Also... Could nanoplasmosis be distributed in the form of pills?
