Identifying Risk Factors for HIV And Syphilis Coinfections in Kwazulu-Natal, South Africa

Abstract

South Africa bears one of the highest burdens of both HIV and syphilis worldwide. Syphilis is caused by the bacterium treponema pallidum and has biological interactions with HIV, leading to accelerated transmission and clinical progression. Understanding shared risk factors among people living with HIV (PLHIV) can inform strategies to prevent and treat these sexually transmitted infections. Methods: From 2013 to 2017, 2,580 PLHIV were enrolled in a cohort from the iThembalabantu Clinic in Umlazi, South Africa. Participants provided clinical, demographic, and behavioral data. Poisson regression assessed associations between coinfection and participant characteristics via prevalence ratios. Results: Among those who tested positive for HIV, 123 (4.7%) were concurrently positive for treponema pallidum. Younger age (PR 0.76 per 10-year increase, p<0.01), male circumcision (PR 0.38, p<0.05), having an HIV-positive partner (PR 1.93, p<0.05), cigarette use (PR 1.52, p<0.05) were associated with coinfection. When these variables were in a combined model, only having an HIV-positive partner remained statistically significant. Conclusions: Having a partner with HIV, younger age, and tobacco use were significant risk factors for syphilis coinfection among PLHIV. These findings highlight the interconnectedness of networks and the need for targeted interventions in high-burden areas with limited healthcare access to mitigate associated morbidity and mortality.