There is multicausal stuff going on here...like we've talked about dry sex being one of them..refusal to wear a condom.
Here's another interesting article about how Malaria increases the rate of infection.http://www.msnbc.msn.com/id/16095390/
I think it's interesting how in Africa having a foreskin "causes" hiv infections to rise according to the US media. But in other countries it is unsafe sex practices which cause HIV risk.
Only safer sexual practices will protect you from aquiring HIV. African countries are so desperate apparently they want to try anything at this point. Though, remember the US has the highest infection rate of a developed country AND is the only one where the majority of men are circ'd. So, that experiment here doesn't work.
And, what about these studies in Africa...did it track the corresponding rate of infection in women? Dry sex with a circumcised penis is definitely going to cause more tears than sex with an intact one. More friction and more tearing with a circumcised penis. But, hey...who cares about the women, right