Development and validation of multiplex assays for mouse and human IgG and IgA to Neisseria gonorrhoeae antigens.

There is an urgent need for vaccines against Neisseria gonorrhoeae (Ng), the causative agent of gonorrhea. Vaccination with an outer-membrane vesicle (OMV)-based Neisseria meningitidis (Nm) vaccine provides some protection from Ng; however, the mechanisms underlying this cross-protection are unknown. To address this need, we developed multiplexed bead-based assays for the relative quantification of human and mouse IgG and IgA against Ng antigens. The assays were evaluated for analyte independence, dilutional linearity, specificity, sensitivity, intra- and inter-assay variability, and robustness to sample storage conditions. The assay was then used to test samples from mice and humans immunized with an Nm-OMV vaccine.

Experimental Urethral Infection with Neisseria gonorrhoeae.

Gonorrhea rates and antibiotic resistance are both increasing. Neisseria gonorrhoeae (Ng) is an exclusively human pathogen and is exquisitely adapted to its natural host. Ng can subvert immune responses and undergoes frequent antigenic variation, resulting in limited immunity and protection from reinfection. Previous gonococcal vaccine efforts have been largely unsuccessful, and the last vaccine to be tested in humans was more than 35 years ago. Advancing technologies and the threat of untreatable gonorrhea have fueled renewed pursuit of a vaccine as a long-term sustainable solution for gonorrhea control. Despite the development of a female mouse model of genital gonococcal infection two decades ago, correlates of immunity or protection remain largely unknown, making the gonococcus a challenging vaccine target. The controlled human urethral infection model of gonorrhea (Ng CHIM) has been used to study gonococcal pathogenesis and the basis of anti-gonococcal immunity. Over 200 participants have been inoculated without serious adverse events. The Ng CHIM replicates the early natural course of urethral infection. We are now at an inflexion point to pivot the use of the model for vaccine testing to address the urgency of improved gonorrhea control. Herein we discuss the need for gonorrhea vaccines, and the advantages and limitations of the Ng CHIM in accelerating the development of gonorrhea vaccines.

Post-randomization Differences in Condomless Vaginal Sex Among Women Randomized to Intramuscular Depot Medroxyprogesterone Acetate Injections, a Copper Intrauterine Device or a Levonorgestrel Implant in the ECHO Trial.

The Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial found no substantial difference in HIV acquisition risk between women randomised to injectable intramuscular depot medroxyprogesterone acetate (DMPA-IM), copper intrauterine device (Cu-IUD) or the levonorgestrel (LNG) implant. We evaluated post-randomization sexual behavior using an objective marker of condomless vaginal sex in a subset of participants. We conducted a sub-study among 458 ECHO participants at three sites (Cape Town, Johannesburg, Kisumu) to evaluate the frequency of condomless vaginal sex, measured by prostate specific antigen (PSA) detection in vaginal swabs, collected at the month 6 and final visit and the concordance of self-reported condomless vaginal sex with PSA detection, by randomized arm. We compared PSA detection frequency and concordance of PSA and self-reported condomless vaginal sex, by randomized group using Cochran-Mantel-Haenszel tests and adjusted generalized logistic growth curve models. PSA was detected less frequently in the DMPA-IM (16%), compared to the Cu-IUD (21%) and LNG implant (24%) groups, although results were not statistically significant in the unadjusted model when accounting for pre-specified multiple-testing criteria. There were significant differences in PSA detection between the DMPA-IM and LNG-implant groups (odds ratio 0.61 (95% CI 0.40, 0.94) in the adjusted model. There was moderate discordance between self-reported condomless vaginal sex and detection of PSA that was similar across randomized groups. These data suggest that women randomized to Cu-IUD and LNG implant may have had condomless sex more frequently than women randomized to DMPA-IM. The discordance between detectable PSA and self-reported sexual behaviour has important implications for design of future HIV prevention studies.

Gentamicin Susceptibility in Neisseria gonorrhoeae and Treatment Outcomes for Urogenital Gonorrhea After 25 Years of Sustained Gentamicin Use in Malawi.

BACKGROUND: Gentamicin has been used for the treatment of gonorrhea in Malawi since 1993. However, declining clinical cure rates have been suspected. We evaluated current Neisseria gonorrhoeae susceptibility to gentamicin in vitro and clinically. METHODS: Men with acute urethritis were recruited at the Bwaila District Hospital STI Clinic in Lilongwe, Malawi, between January 2017 and August 2019. All men provided urethral swabs for etiological testing at enrollment and test of cure (TOC), 1 week later, using Gram-stained microscopy and culture. We used Etest to determine minimum inhibitory concentrations (MICs) of gentamicin, azithromycin, cefixime, ceftriaxone, ciprofloxacin, and spectinomycin; disc diffusion for tetracycline susceptibility; and whole-genome sequencing (WGS) to verify/refute treatment failure. RESULTS: Among 183 N. gonorrhoeae culture-positive men enrolled, 151 (82.5%) had a swab taken for TOC. Of these 151 men, 16 (10.6%) had a positive culture at TOC. One hundred forty-one baseline isolates were tested for gentamicin susceptibility using Etest: 2 (1.4%), MIC = 2 µg/mL; 111 (78.7%), MIC = 4 µg/mL; and 28 (19.9%), MIC = 8 µg/mL. All isolates were susceptible to azithromycin, cefixime, ceftriaxone, and spectinomycin, whereas 63.1% had intermediate susceptibility or resistance to ciprofloxacin. Almost all (96.1%) isolates were resistant to tetracycline. All examined isolates cultured at TOC (n = 13) had gentamicin MICs ≤8 µg/mL. Ten men had pretreatment and posttreatment isolates examined by whole-genome sequencing; 2 (20%) were verified new infections (4119 and 1272 single-nucleotide polymorphisms), whereas 8 (80%) were confirmed treatment failures (0-1 single-nucleotide polymorphism). CONCLUSIONS: Gentamicin MICs poorly predict gonorrhea treatment outcome with gentamicin, and treatment failures are verified with gonococcal strains with in vitro susceptibility to gentamicin. The first-line treatment of gonorrhea in Malawi should be reassessed.

What's Sex Got to Do With It? Understanding Potential Confounding and Exposure Misclassification in Mechanistic Sexually Transmitted Infection Research.

We conducted a prospective study of 13 heterosexual couples to understand the impact of recent condomless vaginal sex on vaginal immune marker measurement and potential exposure misclassification due to the presence of semen. All immune markers were detectable in semen and concentrations of vaginal immune markers varied by sex recency.

A Silent Epidemic: The Prevalence, Incidence and Persistence of Mycoplasma genitalium Among Young, Asymptomatic High-Risk Women in the United States.

Background: Mycoplasma genitalium can result in pelvic inflammatory disease and adverse pregnancy outcomes. We analyzed data collected from a prospective study of asymptomatic bacterial vaginosis (BV) to determine the natural history of M. genitalium. Methods: Women aged 15-25 years, with asymptomatic BV and ≥2 risk factors for sexually transmitted infection were recruited from 10 sites throughout the United States. Vaginal swab samples were collected at enrollment and through home-based testing every 2 months over 12 months. M. genitalium nucleic acid amplification testing was performed for M. genitalium using transcription-mediated assays (Hologic). The prevalence, incidence, and persistence of M. genitalium, defined as all positive specimens during follow-up, were estimated with 95% confidence intervals (CIs). Adjusted odds ratios (AOR) were calculated using logistic and Poisson regression to evaluate participant characteristics associated with M. genitalium infection. Results: Among 1139 women, 233 were M. genitalium positive, for a prevalence of 20.5% (95% CI, 18.2%-22.9%); 42 of 204 had persistent M. genitalium (20.6%). Among 801 M. genitalium-negative women at baseline, the M. genitalium incidence was 36.6 per 100 person-years (95% CI, 32.4-41.3). Black race (AOR, 1.92; 95% CI, 1.09-3.38), age ≤21 years (1.40; 1.03-1.91), and prior pregnancy (1.36; 1.00-1.85) were associated with prevalent M. genitalium; only black race was associated with incident M. genitalium (P = .03). Conclusions: We identified high rates of prevalent, incident, and persistent M. genitalium infections among young, high-risk women with asymptomatic BV, supporting the need for clinical trials to evaluate the impact of M. genitalium screening on female reproductive health outcomes.

Socioeconomic Vulnerability and Sexually Transmitted Infection Among Pregnant Haitian Women.

BACKGROUND: Despite evidence that education and poverty act through distinct pathways to influence sexually transmitted infection (STI), few studies have examined the unique, independent associations of these socioeconomic vulnerabilities with sexual risk behaviors and STI among women. METHODS: From August to October 2013, women at an antenatal clinic in Gressier, Haiti, were interviewed and tested for chlamydial infection, gonorrhea, and trichomoniasis (N = 200). We measured low educational attainment as less than 9 years of schooling and currently living in poverty based on crowding, defined as more than 2 people sleeping in one room. We used logistic regression to estimate independent associations between each socioeconomic indicator and outcomes of sexual behaviors and STI. RESULTS: Approximately 29% of the sample had a current STI (chlamydia, 8.0%; gonorrhea, 3.0%; trichomoniasis, 20.5%), with 2.5% testing positive for more than 1 STI. Forty percent of the sample reported low educational attainment and 40% reported current poverty. Low educational attainment was associated with early risk behaviors, including twice the odds of earlier sexual debut (adjusted odds ratio [AOR], 2.09; 95% confidence interval [CI],: 1.14-3.84). Poverty was associated with reporting the current main sexual partner to be nonmonogamous (AOR, 2.01; 95% CI, 1.00-4.01) and current STI (AOR, 2.50; 95% CI, 1.26-4.98). CONCLUSIONS: Education and poverty seem to independently influence STI behaviors and infection, with low education associated with early sexual risk and poverty associated with current risk and infection. Improving women's educational attainment may be important in improving risk awareness, thereby reducing risky sexual behaviors and preventing a trajectory of STI risk.

Validation of the Cepheid GeneXpert for Detecting Ebola Virus in Semen.

BACKGROUND: Ebola virus (EBOV) RNA persistence in semen, reported sexual transmission, and sporadic clusters at the end of the 2013-2016 epidemic have prompted recommendations that male survivors refrain from unprotected sex unless their semen is confirmed to be EBOV free. However, there is no fully validated assay for EBOV detection in fluids other than blood. METHODS: The Cepheid Xpert Ebola assay for EBOV RNA detection was validated for whole semen and blood using samples obtained from uninfected donors and spiked with inactivated EBOV. The validation procedure incorporated standards from Clinical and Laboratory Standards Institute and Good Clinical Laboratory Practices guidelines for evaluating molecular devices for use in infectious disease testing. RESULTS: The assay produced limits of detection of 1000 copies/mL in semen and 275 copies/mL in blood. Limits of detection for both semen and blood increased with longer intervals between collection and testing, with acceptable results obtained up to 72 hours after specimen collection. CONCLUSIONS: The Cepheid Xpert Ebola assay is accurate and precise for detecting EBOV in whole semen. A validated assay for EBOV RNA detection in semen informs the care of male survivors of Ebola, as well as recommendations for public health.

Evaluation of Herpes Simplex Virus Type 2 Serological Tests for Use With Dried Blood Spots in Kenya.

We evaluated 2 assays to detect antibodies to herpes simplex virus type 2 in dried blood spots prepared from blood specimens submitted to a reference laboratory in Kenya. Dried blood spots did not perform well with the Kalon herpes simplex virus type 2 assay. Focus HerpeSelect 2 was 98.8% sensitive and 98.9% specific with dried blood spots.

Vaginal Prostate Specific Antigen (PSA) Is a Useful Biomarker of Semen Exposure Among HIV-Infected Ugandan Women.

The practical feasibility of using prostate specific antigen (PSA) as a biomarker of semen exposure was examined among HIV-infected Ugandan women. Vaginal fluids were obtained with self-collected swabs and a qualitative rapid test (ABAcard®p30) was used to detect PSA. Trained laboratory technicians processed samples on-site and positive PSA tests were compared to self-reported unprotected vaginal sex (UVS) in the last 48 h. A total of 77 women submitted 126 samples for PSA testing at up to three study visits. Of these samples, 31 % (n = 39/126) were PSA positive, and 64 % (n = 25/39) of the positive PSA samples were accompanied by self-report of no UVS at the study visit the PSA was collected. There were no reported difficulties with specimen collection, storage, or processing. These findings provide preliminary data on high levels of misreported UVS among HIV-infected Ugandan women using practically feasible methods for PSA collection and processing.

Sexual Relationship Power and Semen Exposure Among Female Patients at a Sexually Transmitted Infection Clinic in Kingston, Jamaica.

Women's power in sexual relationships is thought to be an important predictor of condom use. However, research on correlates of condom use often relies on participant reporting of behavior, which has questionable validity. We evaluated the association between scores from the modified Sexual Relationship Power Scale (SRPS-M) and biological detection of semen exposure in a prospective study of adult women attending a sexually transmitted infection clinic in Kingston, Jamaica with cervicitis or abnormal vaginal discharge in 2010-2011. At enrollment, women were counseled to avoid sex while on treatment and were asked to return in 6 days for a follow-up visit. At both study visits, women were administered a questionnaire and had vaginal swabs collected to test for prostate-specific antigen (PSA), a biological marker of recent semen exposure. We found no significant association at enrollment or follow-up between SRPS-M scores and semen exposure, as measured with either self-reported data or PSA positivity. Semen biomarkers could be used to develop and validate new scales on relationship power and self-efficacy related to condom use.

Rapid Diagnosis of Trichomonas vaginalis by Testing Vaginal Swabs in an Isothermal Helicase-Dependent AmpliVue Assay.

BACKGROUND: The AmpliVue Trichomonas Assay (Quidel) is a new Federal Drug Administration-cleared rapid test for qualitative detection of Trichomonas vaginalis (TV) DNA in female vaginal specimens. The assay is based on BioHelix's helicase-dependent amplification isothermal technology in conjunction with a disposable lateral-flow detection device, with a total turnaround time of approximately 45 minutes. OBJECTIVE: The objective of this study was to compare the performance of this new assay to wet preparation and culture as well as to another Federal Drug Administration-cleared nucleic acid amplification assay. METHODS: Four clinician collected vaginal swabs were obtained from women attending sexually transmitted disease, family planning, and OB/GYN clinics and tested by AmpliVue Trichomonas Assay and comparator tests: saline microscopy, TV culture (InPouch), and Aptima TV. AmpliVue Trichomonas Assay results were compared with a composite positive comparator (CPC) as determined by the results from culture and/or wet mount microscopic examination. At least one of either the wet preparation or culture reference test results was required to be positive to establish CPC. RESULTS: A total of 992 patients, 342 symptomatic and 650 asymptomatic patients, were included in the study. Results for AmpliVue for all women combined compared with saline microscopy and culture as a CPC yielded a sensitivity of 100%. Specificity for all women was 98.2%. Overall percent agreement versus Aptima TV was 97.8%. Sensitivity for AmpliVue compared with Aptima was 90.7% %, whereas specificity was 98.9%. CONCLUSIONS: The rapid AmpliVue Trichomonas Assay performed as well as microscopy and culture, and had comparable sensitivity and specificity to another nucleic acid amplification test for the detection of TV. This study provided evidence of new diagnostic options and indicated very good performance of amplified testing for detection of TV in symptomatic and asymptomatic women.

Borderline Personality Disorder Symptom Severity and Sexually Transmitted Infection and HIV Risk in African American Incarcerated Men.

BACKGROUND: Sexually transmitted infections (STI)/HIV rates are disproportionately high among men involved in the criminal justice system. Mental health disorders, including personality disorders, are also elevated among inmates. Borderline personality disorder (BPD) may be an important risk factor for STI/HIV, yet remains relatively understudied, particularly among inmates. METHODS: We used baseline data from Project DISRUPT, a cohort study of African American men being released from prison in North Carolina who were in heterosexual relationships at prison entry (n=189), to assess their STI/HIV risk in the 6 months before incarceration and BPD symptoms focused on emotional lability and relationship dysfunction. We created a continuous BPD symptom severity score and a dichotomous BPD indicator split at the top quartile of the score (BPD-TQ) to examine associations between BPD and STI/HIV outcomes using logistic regression. We also examined associations between individual symptoms and outcomes. RESULTS: After adjustment for sociodemographics and antisocial personality disorder, BPD-TQ was associated with sexual risk behaviors including multiple partnerships (adjusted odds ratio, 2.58; 95% confidence interval, 1.24-5.36) and sex with nonmonogamous partners (adjusted odds ratio, 2.54; 95% confidence interval, 1.17-5.51). Prevalence of previous STI (47.5% vs. 29.6%) and prevalent chlamydial infection (6.9% vs. 3.1%) seemed higher in those in BPD-TQ, although the associations were not statistically significant. Associations were similar to those with the continuous score. Borderline personality disorder symptoms most associated with STI/HIV risk were abandonment worry, mood swings, and shifts in opinions. CONCLUSIONS: Borderline personality disorder is strongly associated with STI/HIV risk in this sample. Researchers should further evaluate the relationship between STI/HIV and BPD, in addition to mood disorders.

A Review of Evidence-Based Care of Symptomatic Trichomoniasis and Asymptomatic Trichomonas vaginalis Infections.

Trichomonas vaginalis is the most prevalent nonviral sexually transmitted infection, affecting an estimated 3.7 million women and men in the United States. Health disparities are prominent in the epidemiology of this infection, which affects 11% of women aged ≥40 years and a disproportionately high percentage of black women. Particularly high prevalences have been identified among sexually transmitted disease (STD) clinic patients and incarcerated individuals. This article reviews and updates scientific evidence in key topic areas used for the development of the 2015 STD Treatment Guidelines published by the Centers for Disease Control and Prevention. Current evidence is presented regarding conditions associated with Trichomonas vaginalis infection, including human immunodeficiency virus (HIV) and pregnancy complications such as preterm birth. Nucleic acid amplification tests and point-of-care tests are newly available diagnostic methods that can be conducted on a variety of specimens, potentially allowing highly sensitive testing and screening of both women and men at risk for infection. Usually, trichomoniasis can be cured with single-dose therapy of an appropriate nitroimidazole antibiotic, but women who are also infected with HIV should receive therapy for 7 days. Antimicrobial resistance is an emerging concern.

Disclosure of HSV-2 serological test results in the context of an adolescent HIV prevention trial in Kenya.

OBJECTIVES: Herpes simplex virus type 2 (HSV-2) biomarkers are often used in adolescent sub-Saharan HIV prevention studies, but evaluations of test performance and disclosure outcomes are rare in the published literature. Therefore, we investigated the proportion of ELISA-positive and indeterminate samples confirmed by western blot (WB), the psychosocial response to disclosure and whether reports of sexual behaviour and HSV-2 symptoms are consistent with WB confirmatory results among adolescent orphans in Kenya. METHODS: In 2011, 837 Kenyan orphan youth in grades 7 and 8 enrolled in an HIV prevention clinical trial with HSV-2 biomarker outcomes. We used a modified algorithm for the Kalon HSV-2 ELISA to improve specificity; positive and indeterminate results were WB tested. We developed culturally sensitive protocols for disclosing positive results, and documented psychosocial responses, reports of sexual contact and HSV-2 symptoms. RESULTS: 28 adolescents (3.3%) were identified as HSV-2 seropositive, six as indeterminate. Of these, 22 positive and all indeterminates were WB tested; 20 and 5, respectively, were confirmed positive. Most youth reported moderate brief stress after disclosure; 22% reported longer and more severe distress. Boys were more likely to be in the latter category. Self-reported virginity was highly inconsistent with WB-confirmed positives. CONCLUSIONS: The higher than manufacturer's cut-off for Kalon ELISA modestly reduced the rate of false-positive test results, but also increased false negatives. Investigators should consider the risk:benefit ratio in deciding whether or not to disclose HSV-2 results to adolescent participants under specific field conditions. TRIAL REGISTRATION NUMBER: NCT01501864.

Differences in misreporting of sexual behavior over time: implications for HIV trials.

We used data from a prospective study of 300 women attending a sexually transmitted infection clinic in Kingston, Jamaica, to compare participant self-report of recent semen exposure to actual semen exposure measured by prostate-specific antigen in vaginal swabs. Underreporting of semen exposure was significantly more frequent at follow-up than baseline, suggesting that the accuracy of reports of sexual behavior may vary over time.

Prostate-specific antigen is unlikely to be a suitable biomarker of semen exposure from recent unprotected receptive anal intercourse in men who have sex with men.

A biomarker of unprotected receptive anal intercourse could improve validity of sexual behavior measurement. We quantified prostate-specific antigen (PSA) from rectal swabs from men who have sex with men (MSM). One swab was PSA positive. Using current methods, PSA is an inadequate biomarker of recent unprotected receptive anal intercourse in men who have sex with men.

Use of HIV and HSV-2 biomarkers in sub-saharan adolescent prevention research: a comparison of two approaches.

Self-report of sexual behavior among adolescents is notoriously inconsistent, yet such measures are commonly used as outcomes for human immunodeficiency virus (HIV) prevention intervention trials. There has been a growing interest in the use of HIV and other sexually transmitted disease biomarkers as more valid measures of intervention impact in high HIV prevalence areas, particularly in sub-Saharan Africa. We examine the challenges, benefits, and feasibility of including HIV and herpes simplex virus type 2 (HSV-2) biomarker data, with details about different data collection and disclosure methods from two adolescent prevention trials in Kenya and Zimbabwe. In Kenya, whole blood samples were collected using venipuncture; adult guardians were present during biomarker procedures and test results were disclosed to participants and their guardians. In contrast, in Zimbabwe, samples were collected using finger pricks for dried blood spots (DBS); guardians were not present during biomarker procedures, and results were not disclosed to participants and/or their guardians. In both countries, prevalence in the study samples was low. Although the standard of care for testing for HIV and other sexually transmitted infections includes disclosure in the presence of a guardian for adolescents under age 18, we conclude that more research about the risks and benefits of disclosure to adolescents in the context of a clinical trial is needed. Notably, current serological diagnosis for HSV-2 has a low positive predictive value when prevalence is low, resulting in an unacceptable proportion of false positives and serious concerns about disclosing test results to adolescents within a trial. We also conclude that the DBS approach is more convenient and efficient than venipuncture for field research, although both approaches are feasible. Manufacturer validation studies using DBS for HSV-2, however, are needed for widespread use.

Evaluation of self-directed specimen collection for chlamydia and gonorrhea testing among people who use drugs.

Background: People who use drugs (PWUD) often have elevated sexually transmitted infection (STI) risk and unmet healthcare needs. Self-directed STI specimen collection (i.e., individuals collect the specimen and mail to the laboratory) may be valuable in addressing STI testing barriers among PWUD. Methods: Within a cohort study among PWUD in New York City, we conducted a cross-sectional substudy from November 2021-August 2022 assessing sexual health with a one-time online survey (n = 120); participants could opt-in to receive a self-collection kit. Participants who opted-in were mailed a kit containing collection materials (males: urine cup, females: vaginal swab), pre-paid return label, instructions, and educational information. Specimens were sent to the laboratory and tested for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC). We measured the number of kits requested, delivered, mailed to the lab, and CT/GC positive; and examined differences in requesting a kit by sociodemographic and behavioral characteristics. Results: Sixty-three total kits were requested by 44 unique participants. Of the 63 requested, 41 were delivered; one kit was undeliverable at the provided address and the rest were not sent due to no address provided or being duplicate requests. Of the 41 kits delivered, three participants returned the kit to the lab; of those, one was positive for CT and GC. The greatest differences in those who did and did not request a kit were observed by age, sexual orientation, past-year sex trade and casual partnerships, and experiences of relationship violence. Conclusions: Self-directed specimen collection may be desirable for PWUD, but research is needed to understand barriers to this testing approach for this population.

Modern diagnosis of Trichomonas vaginalis infection.

Recent advances in tests for the sexually transmitted protozoan parasite Trichomonas vaginalis have increased opportunities for diagnosis and treatment of this important sexually transmitted infection. This review summarises currently available tests, highlighting their performance characteristics, advantages and limitations. The recent development of molecular tests for the detection of T vaginalis, including rapid antigen detection and nucleic acid amplification tests, has significantly improved the quality of diagnostics for trichomoniasis, particularly in women. In light of the expanded menu of testing options now available, improved recognition and better control of trichomoniasis are in sight, which should enable the eventual reduction of adverse reproductive consequences associated with T vaginalis infection.