Globally, the rates of sexually transmitted infections (STIs) are highest among 15-24 year old girls, especially in Sub-Saharan African countries where the adolescent sexual health is poor. Recruiting girls pre-sexual debut could identify risk factors for STI acquisition.
We recruited a prospective cohort of “low-risk” adolescent girls aged 16-20 in Kenya. To be eligible, girls were HIV and HSV-2 seronegative and reported no history of sexual intercourse or reported having sex with only one partner. Demographic data was collected, and girls had nucleic acid testing of vaginal swabs for Neisseria gonorrhea, Chlamydia trachomatis, and Trichomonas vaginalis, and vaginal gram stains for bacterial vaginosis (BV).
We enrolled 400 girls, with a median age of 18.6 years. In this cohort, 322 (80.5%) girls reported never having had sex, while 78 (19.5%) reported prior sex with 1 partner. Of those reporting prior sex, only 20 (25.6%) reported contraception use in the last 3 months, with 60% using only emergency contraceptive pills. The median age of sexual partners was 22 (IQR 19-25). Of the 373 participants with an STI swab result, 49 participants (13.1%) tested positive for STIs at entry into the study, with 41 chlamydia, 5 gonorrhea, and 3 trichomonas cases. Of these 49 participants, 33 (67.3%) had denied prior sexual intercourse. Testing positive for STIs was however significantly different among those reporting prior sexual intercourse vs reporting never having had sex, 21.1% vs 11.1% (p = 0.02). BV was rare (5.6%) in the cohort, with 90% of participants with a normal Nugent score of 0 to 3.
In the initial testing of a sexually inexperienced cohort of girls, we found unexpectedly high numbers of prevalent STIs, especially chlamydia which is not routinely screened for in Kenyan settings. Additionally, lack of sexual activity appeared overreported. BV was rare, with much lower prevalence than in adult women in Africa. Our data suggest that prior to initiation of sexual activity, most girls in this Kenyan cohort have vaginal microflora that is dominated by Lactobacillus. Interventions to address STIs, including pre-exposure prophylaxis for HIV, should be targeted at girls at a young age, pre-sexual debut, and in non-medical settings where girls can be reached who do not self-identify as at risk for STI.
S. Selke, None
L. Oluoch, None
A. Magaret, None
K. Ngure, None
A. Wald, None
N. Mugo, None
A. C. Roxby, None