User blog comment:GrandMethuselah67/Neutral 'verse Character Sheet: Ezra Immaniuel/@comment-4867780-20151116023800/@comment-26322734-20151116034621

A little bit of both. Ezra is a collective entity, but only in the sense that the sentient minds he absorbs exist within him at the basest level of consciousness (kinda in a low-activity dreamlike state). The multitude of sentient minds (including the bacteria themselves) all work together autonomously to create one single superconsciousness, "Ezra". The concept is kinda like the Geth from Mass Effect.

Yeah, I remember reading that Reed is made of "plial bacterial stacks", single cells that duplicate most of the functions in his body. It's why he has self-sustainance and such, and why he's not even really considered human anymore.