The procedure originally had religious motivation
It was started and perpetuated by religious fanatics. I suspect this new "medical evidence" has been manufactured to support their continued practice of circumcision. The first thing fundies want control of is sexual behaviour. They are losing support for completely different reasons among educated westerners, and circumcision is losing major support in western nations even among people who identify themselves as religious, basically because they don't want to hurt babies, and circumcision does exactly that. I guess the fundies feel they are more able to scare utterly uneducated africans into following their religious practice using the AIDS epidemic as a justification.