Impact of recurrent sexually transmitted infections on HIV seroconversion: Results from multi-state frailty models

Impact of marital status on risk of HIV in South Africa (2002-2017)

After decades of research, South African women continue to have the highest burden of HIV in the world. The aim of the study is to investigate the impact of marital status on HIV using population and community-level data sources. We included data 13,469 and 5682 South African women who participated to South African HIV behavioural surveys in 2002-2012 and 2017, respectively. HIV prevalence and incidence rates were significantly higher among single/not-cohabiting women compared to those married/cohabiting with a partner in all survey participants (adjusted odds ratio (aOR): 1.60 and 1.58 in 2002-2012 and 2017, respectively). A quarter of the HIV diagnoses were attributed to those who were single/not-cohabiting women (population attributable risk (PAR%): 25% and 24%, respectively). More than 40% of the HIV infections were exclusively associated with single women (PAR%: 42%, 95% CI: 33%, 51%). Our results provided strong evidence for the profound impact of marital status on excess HIV infection rates. Targeting and reaching single/not-cohabiting women with multiple risk factors can potentially play a crucial role in the trajectories of the epidemic.

Prevalence, incidence and recurrence of sexually transmitted infections in HIV-negative adult women in a rural South African setting

OBJECTIVE

Sexually transmitted infections (STIs), including syphilis, chlamydia, gonorrhoea and trichomoniasis, are of global public health concern. While STI incidence rates in sub-Saharan Africa are high, longitudinal data on incidence and recurrence of STIs are scarce, particularly in rural areas. We determined the incidence rates of curable STIs in HIV-negative women during 96 weeks in a rural South African setting.

METHODS

We prospectively followed participants enrolled in a randomised controlled trial to evaluate the safety and efficacy of a dapivirine-containing vaginal ring for HIV prevention in Limpopo province, South Africa. Participants were included if they were female, aged 18-45, sexually active, not pregnant and HIV-negative. Twelve-weekly laboratory STI testing was performed during 96 weeks of follow-up. Treatment was provided based on vaginal discharge by physical examination or after a laboratory-confirmed STI.

RESULTS

A total of 119 women were included in the study. Prevalence of one or more STIs at baseline was 35.3%. Over 182 person-years at risk (PYAR), a total of 149 incident STIs were diagnosed in 75 (65.2%) women with incidence rates of 45.6 events/PYAR for chlamydia, 27.4 events/100 PYAR for gonorrhoea and 8.2 events/100 PYAR for trichomoniasis. Forty-four women developed ≥2 incident STIs. Risk factors for incident STI were in a relationship ≤3 years (adjusted hazard ratio [aHR]: 1.86; 95% confidece interval [CI]: 1.04-2.65) and having an STI at baseline (aHR: 1.66; 95% CI: 1.17-2.96). Sensitivity and specificity of vaginal discharge for laboratory-confirmed STI were 23.6% and 87.7%, respectively.

CONCLUSION

This study demonstrates high STI incidence in HIV-negative women in rural South Africa. Sensitivity of vaginal discharge was poor and STI recurrence rates were high, highlighting the shortcomings of syndromic management in the face of asymptomatic STIs in this setting.