Recently I thought to myself... "Is Christianity a disease?" After thinking about all the things Christians (Or just any religion in general.) have been responsible for isn't it just to call them a disease? The sheer lose of life from them killing people alone is staggering! What about the technological hindrance they are? Not to mention it's a sort of concern when nuclear-weapon wielding nations think that there will be a glorious end at some point soon. Not to mention the psychological damage done to people who believe it.
Because of this, I'd call it a disease. I prefer to think of the people I know with Christianity as sick and in need of the cure of reason. They're not intentionally poisonous. They just spread what they already have.