Dungeons of Cape Coast Castle

The men were separated from the women and "lived" in the dungeons of the castle. In these dungeons, there were no lights, food, water, etc. They lived and slept in their own feces and vomit. The only time their waste would be taken away was when it rained, the rain water would come through and wash some of it away. On the walls they had a chalk line drawn to the height of where the feces was, about 3 feet. I can't imagine sleeping in my own poop and vomit. How were these people not sick? The conditions were horrendous to say the least.