Why do some South African ethnic groups have very high HIV rates and others not?

The differences in HIV prevalence between South Africa's racial/ethnic groups (19.9%, 3.2%, and 0.5% among 15-49-year-old blacks, coloureds and whites, respectively) are as big as those between the countries with the highest and lowest levels of HIV prevalence worldwide. These large racial/ethnic differences are largely determined by different sexual network structures. In networks among black South Africans, sexual partnerships are more likely to be arranged concurrently - a configuration that leads to exponential increases in the spread of HIV. An examination of the historical origins of polygamy (where it is normative for partnerships to be arranged concurrently) and monogamy (serial or lifetime) reveals that it is the practice of universal monogamy in stratified societies which is the outlier. The ideology and practice of universal monogamy originated in Europe as the result of several factors, most prominently conflicts between the Christian Church and the nobility. After its imposition in Europe, the European colonial project would see this ideology disseminated around the world. Under the influence of liberalism it would mutate into a secular and unacknowledged value-programme of monogamy as a universal norm. This value-programme and practice of monogamy (mostly serial) is still the norm for white South Africans; thus, this sexual behaviour 'spandrel' (by-product of other historical processes) is a large contributor to the lower levels of HIV prevalence among whites. In pre-colonial African societies, polygyny was normative, and the Christian value-programme of monogamy never achieved the hegemonic status it did in Europe and other areas of conquest. Married black African men who converted to Christianity were no less likely to have additional sexual partners, but only more likely to conceal them. The ongoing secrecy about having concurrent partners has contributed to the connectedness of sexual networks among black Africans at large and in this manner has contributed to the rapid spread of HIV.