Problem of Daylight/Approach of Meteors

I was reading some user comments on this series when one comment revealed that half of the world could not be blinded by the meteors because it would be daytime in this half of the world and the glare of the meteor shower would not be seen.Now,the blindness might be caused from some form of radiation or bacteria given off by the meteors so daylight would not stop the blindness.But the path the metour shower would determine what areas of Earth would get hit by high doses of radiation/bacteria vs. other areas hit by weak doses.So,some areas might have escaped the blindness and large infestation of Triffids leading to islands of civilization still control by Man.If someone ,who has read the book or seen this series, has found an explanation for these ideas I have brought up and would give a response to answer my questions;I would appreciate it.