- Quickening redirects here. For the episode, see "The Quickening".
The main visible characteristic of the disease was a series of dark spider-like veins and lesions on the skin, which turned red during the "quickening" or terminal stage of the condition. The disease was caused by a virus. According to Dr. Julian Bashir, differences in physiology between Teplans and other species prevented the contraction of the disease by non-Teplans.
Sufferers of the blight were treated by Bashir on his visit to the Teplan homeworld in 2372. Unfortunately, he learned too late that the Dominion had anticipated modern medical treatment of the disease; the blight was engineered to accelerate through the quickening stage when exposed to electromagnetic fields, including those generated by Bashir's medical devices. As a result, his patients went into agonizing convulsions and begged their resident caretaker, Trevean, for euthanasia.
However, while delivering one dying patient's child, Bashir discovered that an antigen he had administered had prevented the unborn child from contracting the blight. Thus, while the antigen was not a cure for existing sufferers, by initiating a vaccination program the population would be able to eliminate the disease in subsequent generations. (DS9: "The Quickening")
In 2375, Bashir gave a lecture on the disease at a joint Federation-Romulan conference held on Romulus. While there, the chairman of the Tal Shiar, Koval, asked Bashir if the virus could be replicated and introduced into a population, with a view to developing a biogenic weapon.
During one of his lectures at the conference, Bashir explained that in the terminal stages of the disease the lesions become necrotic and there is an increase in leukocyte function. (DS9: "Inter Arma Enim Silent Leges")