I take it that you are not familiar with African customs concerning the dead.
And do african customs relegate to world wide exposure? No.. and do all african nations and people engage in ritualized cleansing? NO. In fact in areas that verbal history speaks of devestating outbreaks, not only are these practices not followed, but houses are built away from one another and not in a close communal location.
To attempt to lump all of "africa" into one behaviour because one behavior is prevalent in a part of Africa is nonsense. Its a continent and its people and tribes and cultures are just as diverse as any other continent on the planet, and are an amalgamtion of their history and communal experiences, and differ greatly from one area to another.