Burden of Sexually Transmitted Infections (STI) in Rural and Peri-Urban KwaZulu-Natal, South Africa: Findings from a Population-Based Household Survey

Abstract

Background: Sexually transmitted infections (STI) contribute to enhancing HIV transmission and acquisition; however, population level prevalence of STI from high HIV burden settings are limited Methods: A population-based household survey undertaken between June 2014 and June 2015 enrolled 15–49 year old males and females in the Vulindlela and Greater Edendale areas of KwaZulu-Natal, South Africa. Data collected includedself-reported sociodemographic, behavioral, and clinical variables. For curable STIs, first-pass urine (males) or self-collected vulvo-vaginal swabs (females) were tested for Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis, Mycoplasma genitalium using multiplex real-time polymerase chain reaction (PCR) and for syphilis serum sample was tested using a non-treponemal rapid plasma reagin (RPR) assay. Herpes simplex virus type 2 (HSV-2) and HIV antibodies were assessed by enzyme-linked immunosorbent assays. Prevalence of all STIs was measured and the association between participant characteristics and curable STIs was estimated using Poisson regression. Findings: Among the 9812 enrolled participants, 38·9% were under the age of 25 years and 63·9% were females. Among males and females, the prevalence of HIV was 28·0% and 44·1%, p<0·001; HSV-2 was 46·1% and 68·8%, p<0·001. Overall, 15·5% of males and 27·8% of females tested positive for any curable STI; syphilis was 1·5% and 1·7%, p=0·62; N. gonorrhoeae 1·8% and 3·7%, p<0·001; C. trachomatis was 5·1% and 9·0%, p<0·001; T. vaginalis was 3·9% and 13·8%, p<0·001 and M. genitalium was 5·7% and 5·2%, p=0·43. Most STIs were higher in females and in HIV positive individuals. Infection with curable STIs in males was associated with age, drug use, and HIV positive status. In females, infection was associated with age, relationship status, number of lifetime partners, concurrent relationship, alcohol use, and HIV status. Viral suppression was associated with lower STI prevalence in both HIV positive males and females. Conclusions: The prevalence of curable STIs, HSV-2 and HIV was high in this population. These findings have important public health implications for HIV transmission and acquisition and justify the importance of population-based surveillance to monitor STIs in order to reduce STI related morbidity and mortality, improve the quality of sexual and reproductive health, and to reduce the STI and HIV syndemic. Funding Statement: Supported by the President’s Emergency Plan for AIDS Relief (PEPFAR) through the Centers for Disease Control and Prevention (CDC) under the terms of operative agreement 3U2GGH000372-02W1. ABMK is supported by the joint South Africa–US Program for Collaborative Biomedical Research from the National Institutes of Health (R01HD083343). Declaration of Interests: All authors declare no competing interests. Ethics Approval Statement: The protocol, informed consent and data collection forms were reviewed and approved by the Biomedical Research Ethics Committee of the University of KwaZulu-Natal, (Reference number BF269/13), and the KwaZulu-Natal Provincial Department of Health (HRKM 08/14). The protocol was also reviewed in accordance with the Centers for Disease Control and Prevention (CDC), United States of America human research protection procedures and was determined to be research, but CDC investigators did not interact with human subjects or have access to identifiable data or specimens for research purposes.