Sexually transmitted infections (STIs) among women enrolled in a Microbicide Development Program (MDP) clinical trial at Durban sites

Abstract

Background: The MDP 301 phase III clinical trial is testing the efficacy and safety of the vaginal microbicide PRO2000/5 in HIV prevention. Infection with sexually transmitted infections (STIs) remains a risk for HIV. We undertook a study to ascertain the prevalence of HIV and STIs among participating women. Methodology: 1452 women were enrolled (November 2005 to August 2007) at MDP sites in Durban, South Africa (Verulam and Tongaat). At enrollment visits, all HIV-negative women aged 18-50 years were screened for syphilis, Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT). Endocervical swabs were taken for NG and CT polymerase chain reaction, and serum for syphilis serology. Infected participants were called back to the clinic. During treatment visits, participants were intensively counseled on consistent condom use. They were issued contact cards for their sexual partners to obtain treatment either at our clinic or at local clinics to avoid re-infections. Marital status was not considered. Results: The mean age of the women was 27 years (range 18-50). 202 (13.9%) were infected with at least one STI at their enrolment visit. 138 (60.8%) infections were in women between the ages of 18-25 years; 46 (20.3%) in those aged 26-35 years; 39 (17.1%) in those aged 36-45 years and 4 (1.8%) in those 46+ years of age. Of the 202 (13.9%) with positive STIs at enrolment, 138 (68.3%) had chlamydia, 42 (20.8%) had gonorrhoea and 38 (18.8%) were positive for syphilis (RPR and TPHA positive). The overall results showed that of the 202 (13.9%) infections, 16 (7.9%) women were infected with more than one STI (i.e. concurrent NG + CT). Conclusion: The high prevalence of STIs suggests that women are at high risk of HIV infection. The prevalence of STIs was highest in younger women, making them particularly vulnerable for HIV infection