Cohort effects on sexual behavior and risk of acquisition of sexually transmitted infections and HIV in a South African HIV prevention trial

Abstract

Introduction: As we approach the fourth decade with human immunodeficiency virus (HIV), a plethora of prevention interventions have been tried; however, prevention of new infections among women remain poorly understood and current behavioral change interventions are simply not working. Material and methods: We investigate whether women's sexual behavior risks vary by age cohort, and the effect of this on HIV and sexually transmitted infections (STI) incidence of women enrolled in the South African Carraguard HIV prevention trial, using Cox proportional hazard models. Results: Relative to women born in the 1960s or earlier, HIV incidence was approximately twice as high compared to women born in the 1970s (adjusted hazard rate [aHR]: 1.91; 95% confidence interval [CI]: 1.04-3.48; p < 0.001). Women in the youngest 1980s cohort had the highest risk of HIV infection (aHR: 3.77; 95% CI: 2.25-6.32; p < 0.001). Similarly, women in the 1980s relative to the oldest (≤ 1960s) cohort had significantly higher hazards of acquiring STIs (aHR: 1.51; 95% CI: 1.16-1.96; p = 0.002), had a higher frequency of partner changes, higher coital frequency, higher proportion having had sex for money, to have an older partner, and less likely to have a circumcised partner. Conclusions: Our findings show HIV and STIs incidence remains highest amongst younger compared to older age cohorts, despite decades of STI/HIV risk-reduction interventions. Research is urgently needed to understand why after so many decades of socio-behavioral interventions little appears to have changed in the behavior of young women; instead, there appears to even be a glamorization of risky behaviors such as having older male sexual partners commonly called 'blessers' .

Understanding the impact of women’s correct risk perception on human immunodeficiency virus diagnosis: Insights from South Africa

“…1,2 Young women have the highest burden of HIV in the region. [2][3][4][5] Poor socioeconomic conditions, cultural and social beliefs as well as risky sexual behaviours such as condomless sex and multiple/concurrent sex partners have been consistently reported as significant contributors to high rates of HIV infections in the region. [6][7][8] As the epidemic continues to spread, nationwide prevention programs have intensified and expanded through the voluntary counselling and testing campaigns, test and treat policy, use of innovative data models such as geospatial mapping to target high risk populations, and the "Focus for Impact Approach" to target vulnerable populations most at risk for HIV (South African National AIDS Council (SANAC) (2017-2022).…”

“…1,2 Young women have the highest burden of HIV in the region. 2–5 Poor socioeconomic conditions, cultural and social beliefs as well as risky sexual behaviours such as condomless sex and multiple/concurrent sex partners have been consistently reported as significant contributors to high rates of HIV infections in the region. 6–8…”

“…We also quantified the relative importance of the risk factors on HIV diagnoses in a multifactorial setting after accounting for their correlations. 5 Understanding the past trends in characteristics and their population-level impacts on HIV infections are crucial for modifying the prevention programs and prioritizing the populations at highest risk of infection. This is the largest study to investigate the key drivers and their changing patterns and impacts on HIV infection over time using a nationally representative sample of black South African women.…”

The HIV Epidemic in South Africa: Key Findings from 2017 National Population-Based Survey

“…Identified socio-behavioural and structural drivers of the HIV epidemic include having multiple sexual partners, condomless sex or inconsistent condom use, socio-economic power imbalances, harmful gender norms, sexual violence, alcohol and substance use [10,15,16]. Other socio-behavioural factors have been associated with HIV vulnerability-the age of sexual debut among youth and age-disparate relationships [17][18][19][20][21]. Age-disparate relationships between young women and older men have been driving the high prevalence of HIV in the country, especially amongst those aged 15-24 years [19,22].…”