I don't think the 'especially' has that implication when you consider the context of the article that we're commenting on. It's true that women and girls make up the majority of people living with HIV worldwide, and this is especially true of the developing world. On the other hand, your statement that "the vast majority of all cases are in men" is simply false. Depending on the interpretation of 'vast', it's arguably not even true in much of the West. For example, in the UK, about a third of people living with HIV are women; in the US it's about a quarter.

There's nothing 'bizarre' about the situation in Africa. People's sexual behaviour is different in different societies, and this can obviously influence how STIs are distributed among different groups in the population.