[CheyennePress]

You want to know what's interesting? This article doesn't include the incidence of asthma in Africa.

And you want to know what else? It's lower than it is in the industrialized world--about the only disease that I can think of that is this way (outside of those induced by distinctly industrial phenomenoms). Funny thing is, low income African-Americans are the most susceptible in the US.

I've seen some evidence that suggests that the parasites that rural Africans are exposed to may decrease the incidence of asthma in the population, priming their immune system to avoid the IgE sensitivity you see with asthma.

[VOA]

It's lower than it is in the industrialized world--about the
only disease that I can think of that is this way (outside of
those induced by distinctly industrial phenomenoms).

IIRC, its the same thing for colon cancer.
The general thought is that the "bulk" in diets in undeveloped
countries keeps food "moving" through the bowel, with little opportunity
to stick around and make mischief for the bowel.