One of the most disturbing impacts of the HIV/ Aids pandemic is that, as more women die, the ratio of men to women has changed, Alan Whiteside, director of the University of Natal's Health Economics and HIV/Aids Research Division says. "The natural gender balance was that there were slightly fewer adult men than women. Now there is a ratio of 120 males to 100 females. This is social engineering like we have never seen before and it is a critical question no one has addressed."