Anal intercourse is an efficient mode of HIV transmission

Anal intercourse is an efficient mode of HIV transmission and may play a role in heterosexual HIV epidemics of southern Africa. However, little information is available on the anal sex practices of heterosexuals in South Africa. Kalichman and colleagues set out to examine the occurrence of anal intercourse in samples drawn from community and clinic settings. Using anonymous surveys collected from convenience samples of 2593 men and 1818 women in two townships and one large city sexually transmitted infections’ clinic in Cape Town, the authors examined measures including demographics, HIV risk history, substance use, and three month retrospective sexual behaviour. A total of 14% (n = 360) men and 10% (n = 172) women reported engaging in anal intercourse in the past three months. Men used condoms during 67% and women 50% of anal intercourse occasions. Anal intercourse was associated with younger age, being unmarried, having a history of sexually transmitted infections, exchanging sex, using substances, having been tested for HIV, and testing HIV positive. Anal intercourse is reported relatively less frequently than unprotected vaginal intercourse among heterosexuals. The low prevalence of anal intercourse among heterosexuals may be offset by its greater efficiency for transmitting HIV. Anal sex should be discussed in heterosexual HIV prevention programming.

Editors’ note: Most research to date has suggested that heterosexual anal intercourse in South Africa is relatively rare. After removing from the dataset the 6% of men who reported same-sex partners in the previous 3 months, this study found that 14% of men and 10% of women reported anal sex over that period. Although heterosexual anal sex was reported more frequently among STI clinic patients than township community members, no differences were found in the proportions of anal intercourse acts protected by condoms. Clearly, a focus on this sexual behaviour that carries a higher risk of HIV acquisition for women should be integrated into HIV prevention programmes aimed at fostering condom-use skills and sexual communication skills.