In this study of young South African women reporting only one lifetime sexual partner, 15% were HIV positive and only two factors were significantly associated with prevalent HIV infection in multivariable analyses. Young women who had not completed high school were more likely to be infected with HIV compared with those that had completed high school. In addition, women who were 20- to 24-years-old were more likely to be infected compared with those ages 15–19 years. Although not statistically significant, women who reported having had an unusual vaginal discharge in the past month, early age of first sex, who did not always use condoms with their main partners and women whose partners had a higher estimated prevalence of HIV were also more likely to be infected.
Education can significantly reduce young women's vulnerability to HIV infection. Compared with less educated peers, better educated women are more likely to delay marriage and childbearing, have fewer children, earn better incomes and have greater decision maker power within relationships.22
In 17 countries in Africa and 4 in Latin America, better-educated girls were found to delay age of first sex and were more likely to use condoms.23
In Zambia, young women with more education were less likely to be HIV infected than those with less education and declines in infection rates from 1995 to 2003 were greatest in young women with the most education.24
In Uganda, HIV infection rates declined the most in young women with a secondary school education.23
Nevertheless, girls face numerous barriers to education. Direct and indirect costs associated with education often prevent young women from attending school.22
In a country such as South Africa where many people live on <1$ a day, the costs of school fees, school uniforms, transportation and books make school attendance an economic impossibility. The primary reason for not completing high school in South Africa is lack of affordability followed second by pregnancy for young women.25
Even in the absence of economic barriers to school attendance, young people, especially young women, are often taken out of school to financially contribute to the household or to take care of sick family members or younger siblings.
Reducing economic barriers to education has been found to increase school attendance and may reduce HIV risk. Children in South African households that receive government social welfare grants are more likely to attend school.26
Cash transfers to families that are conditional upon engaging in behaviours deemed socially beneficial have been used in other parts of the world to encourage children to stay in school. In Mexico, the Progresa program, which provides conditional cash transfers to poor families to send their children to school, has found that the programme increases school enrolment, particularly for girls.27
Reducing the costs associated with school attendance also may reduce risky sexual behaviour. A study in Kenya found that reducing economic barriers to school attendance by paying for girl's school uniforms reduced pregnancy levels and school drop-out rates in those girls.28
Programmes that aim to keep girls in school should be further explored as potential HIV prevention interventions.
As with other studies from sub-Saharan Africa that have aimed to identify behavioural factors associated with HIV infection, we found very few individual level factors that were associated with HIV infection. Access to education is a structural level factor that is not easily modified by the individual, as lack of schools, financial resources and cultural norms often prevent young women from attending school. Other factors identified as increasing the risk of HIV infection, other than the age of the woman, were not individual level factors but rather factors that operate at the level of the woman's partner. Inconsistent condom use and the estimated HIV prevalence of the woman's partner (which increased with the age of her partner) increased the odds that a young woman would be HIV infected, although the associations were not statistically significant. The smaller sample size and analysis for this subgroup within the complex survey framework may have contributed to the imprecision of these estimates. Nevertheless, these factors emphasize the importance of male partners in increasing a woman's risk of infection.
Women aged 20–24 years were significantly more likely to be infected with HIV compared with women aged 15–19 years. Given that women in both age-groups reported having only one lifetime partner, older women might be at increased risk because they reported having sex more frequently than younger women (mean of 2.4 times/month vs 1.6 times/month, respectively) and were in relationship of longer duration than younger women (77% had been in a relationship for >12 months compared with 34% of 15–19-year-old women). Although the age difference between younger and older women and their male partners were similar (the majority had partner 0–4 years older) (data not shown), women who are aged 20–24 years would be more likely to have male partners in an age-group with a higher prevalence of infection. Finally, it is also possible that older women were less truthful about their partner numbers and actually had more lifetime partners and thus were at greater risk.
Although women in this sample reported having only one lifetime partner, 15% were HIV positive. High HIV prevalence levels have also been observed in young women in other sub-Saharan African countries who report one lifetime partner and few acts of sexual intercourse.4
Overall these women report relatively ‘low-risk’ behaviours with regard to factors normally considered ‘high-risk’ for acquiring HIV (e.g. multiple partners, transactional sex, etc.). Only 1% of women in this sample reported having ever engaged in transactional sex and 5% reported early coital debut. Relationship length among women in this sample was on average, close to 2 years, although only 4% of women reported being married (legal or traditional). These young women do not report frequent sex with their partners; almost 45% reported not having sex with their partner in the past month. This raises questions about the nature of these relationships and could indicate that if these young women are in long-term, non-cohabiting relationships where they infrequently have sex with their male partners, their partners may be engaging in concurrent relationships with other women. Concurrency has been found to increase the potential for disease transmission within populations.29
In addition, concurrent relationships also pose risk to the individual; if a male partner acquires HIV from a new partnership, he is significantly more likely to transmit the virus to his main partner during the acute phase of HIV infection than during the latent phase of infection.30
Despite the low risk behavioural profile reported by the women in this sample, a significant proportion acquired HIV in the short span of time that they have been sexually active. We recently reported that the per-partnership probability that a young South African woman would acquire HIV infection if her partner was HIV infected was between 70% and 100%.31
Previous studies from developed countries have found this to be on the average of 30–50%.32
It seems likely that biological factors that increase the efficiency of transmission and acquisition are important within this context. Better understanding the factors that so significantly increase young women's risk of HIV acquisition in sub-Saharan Africa is a critical step in preventing new infections from occurring.
There are several limitations to this analysis. Perhaps most importantly social desirability bias could have resulted in under-reporting of some sexual behaviours (i.e. number of sexual partners) and over-reporting of others (i.e. condom use). Collecting accurate information on self-reported behaviours currently plagues all HIV prevention research.33–35
From our previous research on this sample, there is likely under-reporting of sexual partners by young women.31
Nevertheless, the level of under-reporting at a population level is relatively small. Other studies on sexual behaviour have also reported similar under- and over-reporting.34,35
Methods to improve self-reported behaviours such as Audio Computer Assisted Self Interview (ACASI) or use of biomarkers such as prostate-specific antigen (PSA) may help collect more valid data.36,37
In addition, as these data are cross-sectional, we cannot draw conclusions as to the temporal association between exposures and the outcome of HIV infection. For example, it is possible that young women first acquired HIV infection and then dropped out of school due to illness as opposed to the other way around. This is unlikely, however, as few of the HIV infected individuals in the study knew their status and given their young age, it is probable that they were not infected long enough to be suffering from signs and symptoms related to late stage disease.