P1-S5.14 Risk factors associated with HIV acquisition: a comparative analysis of older and younger women who participated in the MDP301 trial in Johannesburg

Abstract

Conclusion Despite personal experience with HIV, risky sexual behaviours and STI prevalence remain a problem in persons living with HIV in the capital city of Nicaragua. In order to prevent reinfection between serodiscordant partners as well as continued STI transmission, it is important for STI prevention programs to continue to develop their sexual health services, focusing on improved condom access and promotion. Aim To estimate the population attributable risk (PAR) for Chlamydia trachomatis infection in young men and women in Sydney, Australia. Method Multivariate logistic regression was used to examine the association between demographic, sexual behaviour and other potential risk factors on chlamydia positivity in young (#30 years) heterosexual international travellers (backpackers) and Australian residents attending a sexual health clinic. Point and interval estimates of PAR were calculated to quantify the proportion of chlamydia infections that can theoretically be prevented if a combination of risk factors is eliminated from a target population. Results In males, the PAR associated with inconsistent condom use in the past 3 months was 65% (95% CI 56 to 71%) in backpackers compared to 50% (95% CI 41 to 56%) in non-backpackers and the PAR associated with reporting three or more female sexual partners in the past 3 months was similar between male backpackers and non-backpackers; 33% (95% CI 28 to 40%) and 36% (95% CI 32 to 41%), respectively. In females, the PAR associated with inconsistent condom use in the past 3 months was 51% (95% CI 42 to 59%) in backpackers compared to 41% (95% CI 31 to 51%) in non-backpackers, and the PAR associated with reporting three or more male sexual partners in the past 3 months was 14% (95% CI 11 to 18%) in backpackers compared to 30% (95% CI 25 to 37%) in non-backpackers. Conclusion These findings suggest that the largest number of chlamydia infections could be avoided by increasing condom use, particularly in backpackers. Reporting multiple partners was also associated with a large proportion of infections and the risk associated with this behaviour should be included in health promotion strategies. Background Previous studies have shown that recreational drug use is associated with high-risk sexual behaviour and STI. Little is known about the relationship between the use of specific recreational drugs during sex, sexual behaviour and the risk for any STI (chlamydia (CT), gonorrhoea (NG) and/or syphilis) or the three STI separately in heterosexual men, men having sex with men (MSM) and women. We assessed the prevalence of recreational drug use during sex, and assocations of drug use during sex with high-risk sexual behaviour and STI. Methods Attendees of the STI clinic of the Public Health Service of Amsterdam were interviewed during three waves of a bi-annual anonymous survey (2008e2009) about sexual behaviour in the preceding 6 months (number of steady and casual sex partners, condom use during vaginal or anal sex) and specific recreational drug use just before or during...