Young men's HIV risks in South Africa: the importance of multiple risk behaviors

In a recent research letter, Lane et al. ^[1] presented findings regarding heterosexual anal intercourse as a risk factor for HIV infection among young South African men. This research, based on an analysis of data from a nationally representative household survey of youth aged 15-24 years ^[2], assesses the prevalence of heterosexual anal intercourse and its association with HIV infection. This research is welcome, because of the paucity of data on heterosexual anal intercourse as a risk factor for HIV transmission, particularly in African settings. As the authors note, anal intercourse is a potentially significant pathway for HIV transmission, and those who engage in this risk behavior may be less inclined to use condoms, partly because anal sex is erroneously viewed as safer than vaginal intercourse.

In their report, Lane et al. found that young men who engage in anal intercourse were significantly more likely than those experiencing vaginal intercourse only to be HIV infected (odds ratio 2.0, 95% confidence interval 1.3-3.6). Younger men aged 15-19 years were more than four times more likely to be HIV infected than those reporting only vaginal intercourse. Risk factors independently associated with this outcome included more than four lifetime partners, sexual intercourse under the influence of alcohol or drugs, and transactional sex ^[1]. The importance of this finding should not be minimized. However, the fact that anal intercourse may be one of a number of risk behaviors that enhance young men's risk of HIV infection should also be emphasized.

Research on youth HIV-related risk behaviors increasingly suggests that some young men experience a constellation of risk factors, including an early age at sexual debut, the pursuit of multiple and concurrent partnerships, and inconsistent condom use ^[2-4]. Our research in KwaZulu/Natal province suggests that early sexual debut for men, in particular, may be an important factor associated with various subsequent sexual risk behaviors. For example, in our studies of youth and HIV-related risk behaviors, a consistent minority of men, approximately 13-15%, report sexual initiation at the age of 14 years or younger ^[3] (Harrison et al., 2006; in preparation). Often, men with early sexual debut have riskier first sexual experiences than men with an older age at first sex. Furthermore, our findings show that early sexual debut for young men is strongly associated with multiple sexual partnerships in the later teen and young adult years ^[3]. These data reveal patterns of sexual behavior broadly similar to the national youth survey. The prevalence of anal sex was higher (11.7%), but was not independently associated with other sexual risk outcomes (Harrison et al., 2006; in preparation).

Of note is the fact that age of sexual debut did not emerge as a behavioral risk associated with anal intercourse in the report by Lane et al. This may result from the way that the age of sexual debut was categorized. In their analysis, sexual debut was measured as being above or below 17 years of age, the approximate median age at first sex for young men and women in South Africa ^[2,3]. This measure of age at sexual debut thus compares roughly equivalent categories of young people on either side of the median, and does not adequately distinguish those with early debut who may represent a higher risk group. Data from the national youth survey indicate that 12% of young men report sexual debut at the age of 14 years or younger ^[2]. If the data of Lane et al. were re-analysed to examine the association between early sexual debut (i.e. sexual intercourse at 15 years of age or younger) and the practice of anal sex, it is possible that an association would be found.

We do not wish to minimize the importance of these findings, nor to engage in statistical nitpicking. Rather, our aim is to encourage a thorough understanding of the factors that place young South African men at risk of HIV infection. Other research on men in Africa suggests that early sexual behaviors influence risk throughout the life course ^[5]. As Lane et al. note, a high prevalence of anal sex may represent an HIV risk reduction strategy among youth who are avoiding the known risks associated with vaginal intercourse. Equally, however, it may be one of a number of risk behaviors exhibited by a highly vulnerable group of young men. Too little is known about young men's sexual behaviors and their determinants, as well as the social factors that influence them. Prevention efforts should focus not only on increasing the safety of anal sex, or other HIV risk-related behaviors, but rather on comprehensive prevention interventions to promote sexual health while addressing young men's vulnerability and risk in the broader contexts of their lives.

Sponsorship: Support from National Institutes of Health (NIH) training grant NIDA 5T32DA13911 is gratefully acknowledged. Funding for the research mentioned here was received from NIH (R01-37343; R01-HD41721) and Wellcome Trust, UK, as well as additional support from the South African Medical Research Council.