How to avoid traffic from low income countries?

How to avoid traffic from low income countries?

My website works with an affiliate system and google sends me lots of traffic coming from low income countries like indonesia, morocco and african countries.
I just changed the geo targeting in webmaster tools to USA. Nevertheless, i d like to keep google organic traffic from western europe, Japan and Australia.
Is there any ways to prevent being indexed in versions of google that are not profitable for me? (like african countries)
thks.