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Background The Hologic Aptima HIV-1 Quant Assay that is currently available on the Panther system is FDA-cleared for plasma viral load monitoring. We compared to other assays for use with dried blood spots (DBS) and for early infant diagnosis (EID) using plasma and DBS. Methods Spiked dilution panels of plasma and DBS were made using negative donor blood and subtype B and subtype C HIV-1 stocks. Patient samples included plasma from HIV-1-infected adults, plasma from HIV-1-infected infants and exposed uninfected infants, and DBS from infected adults. Samples were run on Aptima Quant and either Abbott RealTime HIV-1 Quant assay or Hologic Aptima HIV-1 Qual assay. Results Aptima Quant and Abbott Quant were comparable: the 95% limit of detection was 42cp/ml for Aptima Quant and 91cp/ml for Abbott Quant. EID comparisons showed that Aptima Quant and Qual had 100% sensitivity and 98.9% specificity with overall agreement between the assays of 98.4%. Aptima Qual had a slightly lower limit of detection (95% limit of detection was 27cp/ml for Aptima Qual and 65 cp/ml for Aptima Quant). With spiked DBS, all 16 DBS with >30cp/ml on Aptima Quant were detected on Aptima Qual, 10/12 (83%) with ‘ Conclusion The Hologic Aptima HIV-1 Quant assay performed similarly for viral load and EID on both plasma and DBS samples. Our data suggest the ‘ Disclosure No significant relationships.

Introduction Vaginal prostate-specific antigen (PSA) is a biomarker of recent semen exposure that may overcome potential fallacies of self-reported sexual behaviours, improving sexual exposure assessment in HIV/STI research. Methods We conducted a cohort study to compare PSA detection and self-reported unprotected sex using data from a clinical trial in Malawi that randomised 73 HIV-infected and 24 HIV-uninfected women to depot medroxyprogesterone acetate injectable or levonorgestrel implant. Women were advised to abstain from vaginal intercourse or use a condom the day preceding study visits. We tested 539 vaginal swabs from 97 women for PSA using the ABAcard p30 rapid strip test (Abacus Diagnostics, Inc., West Hills, CA). Self-reported sexual behaviours and vaginal swabs were collected at six study visits. Log-binomial regression with generalised estimating equations were used to estimate associations of PSA detection and reported unprotected sex with demographic and behavioural factors, adjusting for study arm and pre- vs. post-contraception initiation. Results Overall, 55 (57%) women tested positive for PSA and 54 (56%) women reported unprotected sex. Among PSA-positive samples, 62% (65/105) of instances reported no unprotected sex. The following were associated with PSA detection: HIV-negative status (Prevalence Ratio (PR): 1.69, 95% Confidence Interval (CI):1.09, 2.61), younger age (PR: 1.04, CI: 1.00, 1.08), reported unprotected sex (PR: 2.48, CI: 1.70, 3.60), and sex within past 48 hours (PR: 4.68, CI: 3.00, 7.30). The same factors were significantly associated with self-reported unprotected sex, as was PSA detection (PR: 2.45, CI: 1.7, 3.53). Conclusions Self-reported sexual behaviours were significantly associated with PSA detection. However, PSA was detected among women reporting no unprotected sex, suggesting misreporting of condom use or condom failure. HIV-negative status and younger age were associated with unprotected sex, suggesting more frequent biases in research data for these groups based on social desirability and non-adherence to protocols.

Introduction: Mycoplasma genitalium (MG) is an emerging sexually transmitted infection (STI) associated with cervicitis, pelvic inflammatory disease, and adverse pregnancy outcomes in women, yet little is known regarding its natural history. We conducted a secondary analysis of specimens collected from young women enrolled in a multi-centre study of asymptomatic bacterial vaginosis (BV) in order to determine the natural history of MG and associated factors with infection. Methods Sexually active women aged 15–25 years were recruited from 10 US clinical sites. Eligible women had asymptomatic BV at baseline, and >/=2 STI risk factors. Self-collected vaginal swabs were collected at enrollment, and by home-based testing at 2, 4, 6, 8, 10 and 12 months. MG nucleic acid amplification testing was performed using a transcription mediated assay (Hologic Inc, San Diego, California). Prevalent, incident and persistent MG were estimated with 95% confidence intervals (CI). Univariate analyses and logistic regression modelling were performed to assess associations between participants’ baseline demographic, sexual, and clinical characteristics with prevalent MG infection. Results Specimens were tested for MG from 1365 predominantly Black (85.4%) women. At baseline, 233 women were MG+ (prevalence 20.5% [95% CI: 18.2–22.9]); among 204 participants with follow-up specimens, 42 (20.6%) had persistent MG, remaining MG+ on all follow-up testing. Among 801 women who were MG negative at baseline with follow-up testing, 220 had at least one subsequent MG+ test for an incidence of 27.5% (95% CI: 24.4–30.7). Black race (adjusted odds ratio (AOR) 1.92, 95% CI: 1.09–3.38) and younger (15–21 years) age (AOR 1.40, 95% CI: 1.03–1.91) were significantly associated with prevalent MG infection. Conclusions We identified high rates of prevalent, incident, and persistent MG infections among sexually active young women followed over 12 months. As national programs consider the impact of MG as an STI, the implications of asymptomatic infections should be considered among at-risk populations.