Why is the HIV/AIDS highest in Sub saharan Africa than the Europe?

Cleanliness and being wise. (Like being smart and using meds/etc to prevent it) is what prevents HIV/AIDS. However, when you are in a poor area. And are less fortunate. You cannot buy/afford meds to prevent this. Sometimes this is not always the case. Uncleanliness can leave to AIDS/HIV too. Since sub Saharan Africa has regions of poor ness, this can lead to it.

If you under eat, your bones will narrow.

Eating right and exercising daily