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Non-neutralizing functions of antibodies, including phagocytosis, may play a role in Chlamydia trachomatis (CT) infection, but these functions have not been studied and assays are lacking. We utilized a flow-cytometry-based assay to determine whether serum samples from a well-characterized cohort of CT-infected and naïve control individuals enhanced phagocytosis via Fc-receptor-expressing THP-1 cells, and whether this activity correlated with antibody titers. Fc-receptor-mediated phagocytosis was detected only in CT+ donors. Phagocytosis generally did not correlate well with antibody titer. In addition, we found that complement from both CT+ and negative individuals enhanced phagocytosis of CT into primary neutrophils. These results suggest that anti-CT antibodies can have functions that are not reflected by titer. This method could be used to quantitively measure Fc-receptor-mediated function of anti-CT antibodies or complement activity and could reveal new immune correlates of protection.
Assuntos
Infecções por Chlamydia , Receptores Fc , Humanos , Fagocitose , Neutrófilos , Anticorpos Antibacterianos , Chlamydia trachomatisRESUMO
OBJECTIVE: To determine bacterial vaginosis (BV) status at multiple time points among adolescent girls and young women (AGYW) and assess the impact of pregnancy on their BV status. DESIGN: Longitudinal cohort study. SETTING: Thika, Kenya. PARTICIPANTS: AGYW aged 16-20 years enrolled prior to first sex or reporting only a single lifetime partner. MAIN OUTCOME MEASURES: The primary outcome was relative risk (RR) of BV during pregnancy compared with before pregnancy by analysing longitudinal trends in BV over time. BV risk was estimated using Poisson regression models. RESULTS: A total of 121 AGYW became pregnant in the parent cohort and had BV results before, during or after pregnancy. Point prevalence of BV was 11.0% at visits >12 months pre-pregnancy, 13.0% at 3-12 months pre-pregnancy, 22.1% at <3 months pre-pregnancy and 13.4% during pregnancy. Compared with visits during pregnancy, RR of BV was 1.65 (95% CI: 1.00 to 2.71; p=0.05) at visits <3 months pre-pregnancy, 0.97 (95% CI: 0.62 to 1.52; p=0.90) at visits 3-12 months pre-pregnancy and 0.82 (95% CI: 0.44 to 1.53; p=0.53) at visits 12 months pre-pregnancy. An adjusted analysis including age, income, residence, date of first sex, recent sexual activity and positive sexually transmitted infection test resulted in small changes in risk estimates, with adjusted RR of BV of 1.66 (95% CI: 1.04 to 2.67; p=0.04) at visits <3 months pre-pregnancy compared with visits during pregnancy. CONCLUSIONS: BV risk during pregnancy was lower than during the immediate pre-pregnancy period. Hormonal changes in pregnancy may reduce BV.
Assuntos
Infecções Sexualmente Transmissíveis , Vaginose Bacteriana , Gravidez , Feminino , Adolescente , Humanos , Vaginose Bacteriana/diagnóstico , Vaginose Bacteriana/epidemiologia , Quênia/epidemiologia , Estudos Longitudinais , Infecções Sexualmente Transmissíveis/epidemiologia , Prevalência , Fatores de RiscoRESUMO
Background: Cervical cancer is the leading cause of cancer-related deaths among Kenyan women. Persistent infection with high-risk oncogenic Human papillomavirus (HPV) genotypes is a necessary cause of cervical cancer. HPV vaccines are safe, durable, and efficacious in preventing incident HPV infections. In Kenya, despite efforts to increase HPV vaccination, coverage remains low. We sought to assess: (1) barriers and facilitators of HPV vaccination from the perspective of adolescent girls and young women (AGYW), their guardians as well as stakeholders involved in HPV vaccine delivery, and (2) the acceptability of the single dose of the HPV vaccination among healthcare providers (HCPs). Methods: Our study is nested within the KENya Single-dose HPV-vaccine Efficacy study (KEN SHE) that sought to test the efficacy of single-dose bivalent (HPV 16/18) and single-dose nonavalent (HPV 16/18/31/33/45/52/58/6/11) vaccination. We are conducting this study in Kiambu, Nairobi, and Kisumu counties. In these counties, we are interviewing stakeholders (n = â¼25), selected based on their role in HPV vaccination at the county and national levels. Interviews are audio recorded and conducted in English or Swahili. The semi-structured interview guides were designed based on: (1) the Theoretical Domains Framework (TDF) for AGYW and guardians and (2) the Consolidated Framework for Implementation Research (CFIR) for other stakeholders. The Theoretical Framework of Acceptability (TFA) was leveraged to design the survey administered to HCPs (n = â¼309) involved in HPV vaccination. We will develop a codebook based on emerging codes from the transcripts and constructs from the TDF and CFIR. Emerging themes will be summarized highlighting similarities and differences between and within the different stakeholder groups and counties. Descriptive statistics and a χ2 test will be used to assess the distribution of responses between the different sites and regression analysis will be used to assess factors associated with high acceptability of the single-dose strategy while controlling for confounding variables. Discussion: Our study will describe key barriers and facilitators that affect HPV vaccination from the perspective of multiple stakeholders as well as insights on the perspective of HCPs towards the single-dose strategy to inform the designing of strategies to increase HPV vaccination uptake in Kenya and comparable settings.
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BACKGROUND: Adolescent girls and young women (AGYW) have a high incidence of unplanned pregnancies, especially in low-resource settings. AGYW assess the overlapping risks of pregnancy, contraception, and STIs as they navigate relationships. Few studies have examined how AGYW consider the comparative risks of their decisions around sexual and reproductive health in this context or how risk perception influences contraceptive use. METHODS: Twenty in-depth interviews (IDIs) and 5 focus group discussions (FGDs) were conducted with a subset of sexually active AGYW enrolled in the Girls Health Study (GHS), a longitudinal cohort study in Thika, Kenya, assessing HSV-2 incidence in a cohort of AGYW aged 16-20. Interview questions were focused on perspectives and decision-making around sexual and reproductive health. Interviews were conducted in both English and Kiswahili, transcribed, and coded using inductive and deductive approaches to identify emerging themes. RESULTS: Misconceptions about long-acting reversible contraceptives (LARCs), injectables, and daily oral contraceptive pills strongly disincentivized their use among AGYW. Participants described pregnancy as undesirable, and AGYW reported prioritizing contraceptive methods that were effective and reliable in pregnancy prevention, even if not effective in preventing STI/HIV infection. Participants reported that AGYW relied heavily on emergency contraceptive (EC) pills for pregnancy prevention. CONCLUSIONS: Though the goal of avoiding unintended pregnancy was common, this did not suffice to motivate the uptake of long-term contraceptives among AGYWs. Given the convenience, cost-effectiveness, and lower perceived risk of side effects, EC pills were more likely to be accepted as a form of contraception. Understanding the reasons for AGYW's acceptance of certain contraceptive methods over others can help future interventions better target communication and counseling about contraception and influence key drivers of AGYW behavior and decision-making around sexual and reproductive health.
Assuntos
Infecções por HIV , Infecções Sexualmente Transmissíveis , Gravidez , Humanos , Feminino , Adolescente , Anticoncepcionais , Infecções por HIV/epidemiologia , Quênia , Estudos Longitudinais , Infecções Sexualmente Transmissíveis/prevenção & controle , AtitudeRESUMO
Background: The contraceptive vaginal ring (NuvaRing), one of the Multipurpose Prevention Technologies (MPT) products, is effective in preventing unintended pregnancies and may contribute to reducing the frequency of Bacterial Vaginosis (BV), which is a risk factor for HIV acquisition, transmission, and shedding among women. NuvaRing may cause irregular menstruation, including menstrual suppression, which may influence women's decision on product choice, use, and acceptability. In this prospective cohort study, we assessed women's experiences with menstruation suppression following continued NuvaRing use. Methods: A total of 18 in-depth interviews were conducted using a semi-structured interview guide among purposively selected women with BV in Thika, Kenya, aged 18-40 years, who used NuvaRing continuously. All women received counseling on possibility of menstrual suppression following continuous NuvaRing use. Audio recordings were transcribed verbatim and thematically analyzed. Results: Participants who expected and were aware that menstrual suppression was a possible side effect of Nuvaring accepted its benefits, and expressed acceptance and desire to continue using NuvaRing. Participants who had not anticipated menstrual suppression expressed anxiety and fear, with some expressing desire to continue using NuvaRing but worried about unintended negative consequences. The ability to perform daily activities uninterrupted, reduced expenses on sanitary supplies, enhanced sexual pleasure and relationships, and absence of menstrual pain were benefits of menstrual suppression. Although all participants received counseling on menstrual suppression, some expressed anxiety over the possibility of unintended pregnancy. As a result, they frequented medical facilities for health check-ups and pregnancy tests, and some used combined oral contraceptives to induce menses. Conclusion: Understanding perceptions regarding menstrual suppression is crucial in offering targeted and comprehensive counseling to improve women's understanding of menstruation suppression to influence acceptance and use of NuvaRing. Additionally, improved male involvement in reproductive health concerns and women's autonomy in discussing reproductive health issues with partners is essential.
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BACKGROUND: Bacterial vaginosis is a risk factor for sexually transmitted infections, including HIV. Adult African women have a high prevalence of bacterial vaginosis, but it is not known when first bacterial vaginosis occurs. OBJECTIVE: This study aimed to describe bacterial vaginosis in younger African women, before and after first sex, and to determine the incidence of bacterial vaginosis and significant correlates of bacterial vaginosis incidence and recurrence. STUDY DESIGN: In a prospective observational cohort study enrolling adolescents with limited sexual experience, young women aged 16 to 21 years were recruited in Thika, Kenya. Eligible participants were HIV and herpes simplex virus 2 seronegative and reported 0 or 1 lifetime sexual partner. The Nugent score was determined at quarterly visits from vaginal Gram stains. The trends in bacterial vaginosis were described over time; hazard ratios were calculated using Cox regression, and relative risk of bacterial vaginosis was estimated using generalized estimating equations and Poisson regression. RESULTS: A total of 400 participants with a median age of 18.6 years (interquartile range, 16-21) were enrolled. Of note, 322 participants (80.5%) reported no history of sex, whereas 78 participants (19.5%) reported sex with 1 partner. At enrollment, bacterial vaginosis (Nugent score of ≥7) was uncommon (21/375 [5.6%]). Overall, 144 participants had bacterial vaginosis at least once, for an incidence rate of 16.5 cases per 100 person-years. Before first sex, bacterial vaginosis was present at 2.8% of visits, compared with 13.7% of visits after first sex. An adjusted model of bacterial vaginosis incidence observed that first sex was associated with more than a 2-fold increased bacterial vaginosis risk (adjusted hazard ratio, 2.44; 95% confidence interval, 1.25-4.76; P=.009). Chlamydia diagnosis (adjusted hazard ratio, 1.73; 95% confidence interval, 1.1-2.8; P=.02), and herpes simplex virus 2 seropositivity (adjusted hazard ratio, 2.88; 95% confidence interval, 1.17-7.09; P=.021) were both associated with incident bacterial vaginosis. A multivariate generalized estimating equation model, including all episodes of bacterial vaginosis, demonstrated risk factors, including first sex, sexually transmitted infections, urban residence, recent sex, and no income; the most important risk factor was first sex (adjusted relative risk, 1.92; 95% confidence interval, 1.12-3.31; P=.018). The probability of bacterial vaginosis increased with each subsequent episode; mean Nugent scores increased after each bacterial vaginosis episode. CONCLUSION: Using detailed longitudinal observation, this study found that Kenyan adolescents have almost no bacterial vaginosis before first sex and that initiation of sexual activity was the strongest risk factor for both prevalent bacterial vaginosis and incident bacterial vaginosis.
Assuntos
Infecções por HIV , Infecções Sexualmente Transmissíveis , Vaginose Bacteriana , Adulto , Feminino , Adolescente , Humanos , Quênia/epidemiologia , Incidência , Estudos Prospectivos , Prevalência , Infecções Sexualmente Transmissíveis/epidemiologia , Vaginose Bacteriana/epidemiologia , Vaginose Bacteriana/complicações , Comportamento Sexual , Fatores de Risco , Infecções por HIV/epidemiologia , Infecções por HIV/complicaçõesRESUMO
BACKGROUND: An important cervical cancer prevention strategy in low- and middle-income countries (LMICs) has been single-visit screen-and-treat (SV-SAT) approach, using visual inspection with acetic acid (VIA) and ablative treatment with cryotherapy to manage precancerous lesions. While SV-SAT with VIA and cryotherapy have established efficacy, its population level coverage and impact on reducing cervical cancer burden remains low. In Kenya, the estimated cervical cancer screening uptake among women aged 30-49 is 16% and up to 70% of screen-positive women do not receive treatment. Thermal ablation for treatment of precancerous lesions of the cervix is recommended by the World Health Organization and has the potential to overcome logistical challenges associated with cryotherapy and facilitate implementation of SV-SAT approach and increase treatment rates of screen-positive women. In this 5-year prospective, stepped-wedge randomized trial, we plan to implement and evaluate the SV-SAT approach using VIA and thermal ablation in ten reproductive health clinics in central Kenya. METHODS: The study aims to develop and evaluate implementation strategies to inform the national scale-up of SV-SAT approach with VIA and thermal ablation through three aims: (1) develop locally tailored implementation strategies using multi-level participatory method with key stakeholders (patient, provider, system-level), (2) implement SV-SAT approach with VIA and thermal ablation and evaluate clinical and implementation outcomes, and (3) assess the budget impact of SV-SAT approach with VIA and thermal ablation compared to single-visit, screen-and-treat method using cryotherapy. DISCUSSION: Our findings will inform national scale-up of the SV-SAT approach with VIA and thermal ablation. We anticipate that this intervention, along with tailored implementation strategies will enhance the adoption and sustainability of cervical cancer screening and treatment compared to the standard of care using cryotherapy. TRIAL REGISTRATION: NCT05472311.
Assuntos
Lesões Pré-Cancerosas , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle , Detecção Precoce de Câncer/métodos , Quênia , Estudos Prospectivos , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/cirurgia , Ácido Acético , Programas de Rastreamento/métodos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
PURPOSE: Adolescent girls and young women (AGYW) are disproportionately affected by STIs. Observation of life course events can describe behavioral and biological factors associated with STI risk. METHODS: Sexually inexperienced AGYW aged 16-20 years in Kenya were followed for five years. Quarterly visits assessed for C. trachomatis (CT), N. gonorrhea (GC), and T. vaginalis (TV), bacterial vaginosis (BV), HSV-2, and HIV. Sexual activity was self-reported but amended if incongruent with results from STI, pregnancy, or any other testing. Cox regression and Generalized Estimating Equation models were used to determine hazard ratios (HRs) and relative risks (RRs) of STI. RESULTS: During follow-up, 293 of 400 participants reported sex, 163 AGYW experienced an STI, and 72 participants had multiple STIs. Among 163 participants that experienced an STI, there were a total of 259 visits where STIs were detected, 78% (n = 201) of which included CT. Cox regression found participants with BV had over two-fold higher risk of first STI acquisition (adjusted hazard ratio (aHR): 2.35; 95% confidence interval (CI) 1.43-3.88; p = .001). Increased risk for first STI episode was associated with a new partner (aHR: 3.16; 95% CI 1.59-6.28; p = .001). AGYW who did not disclose sexual activity had the highest risk (aHR: 3.60; 95% CI 1.93-6.70; p < .001). Condom use was low, with 21% reporting condom use with sex. GEE analysis of all STIs including incident, prevalent, and recurrent, confirmed these risk factors. DISCUSSION: During the critical years after first sex, AGYW with BV, new sexual partners, and those who did not disclose sexual activity were at highest risk for STI events, especially CT.
Assuntos
Gonorreia , Infecções por HIV , Infecções Sexualmente Transmissíveis , Vaginose Bacteriana , Gravidez , Adolescente , Feminino , Humanos , Incidência , Quênia/epidemiologia , Infecções Sexualmente Transmissíveis/epidemiologia , Comportamento Sexual , Gonorreia/epidemiologia , Vaginose Bacteriana/epidemiologia , Infecções por HIV/epidemiologiaRESUMO
Background: Adolescent girls and young women (AGYW) are at high risk of sexually transmitted infections (STIs). It is unknown whether beginning to have sexual intercourse results in changes to immune mediators in the cervicovaginal tract that contribute to this risk. Methods: We collected cervicovaginal lavages from Kenyan AGYW in the months before and after first penile-vaginal sexual intercourse and measured the concentrations of 20 immune mediators. We compared concentrations pre- and post-first sex using mixed effect models. We additionally performed a systematic review to identify similar studies and combined them with our results by meta-analysis of individual participant data. Results: We included 180 samples from 95 AGYW, with 44% providing only pre-first sex samples, 35% matched pre and post, and 21% only post. We consistently detected 19/20 immune mediators, all of which increased post-first sex (p<0.05 for 13/19; Holm-Bonferroni-adjusted p<0.05 for IL-1ß, IL-2, and CXCL8). Effects remained similar after excluding samples with STIs and high Nugent scores. Concentrations increased cumulatively over time after date of first sex, with an estimated doubling time of about 5 months.Our systematic review identified two eligible studies, one of 93 Belgian participants, and the other of 18 American participants. Nine immune mediators were measured in at least two-thirds of studies. Meta-analysis confirmed higher levels post-first sex for 8/9 immune mediators (p<0.05 for six mediators, most prominently IL-1α, IL-1ß, and CXCL8). Conclusions: Cervicovaginal immune mediator concentrations were higher in women who reported that they started sexual activity. Results were consistent across three studies conducted on three different continents. Funding: This research was funded by R01 HD091996-01 (ACR), by P01 AI 030731-25 (Project 1) (AW), R01 AI116292 (FH), R03 AI154366 (FH) and by the Center for AIDS Research (CFAR) of the University of Washington/Fred Hutchinson Cancer Research Center AI027757.
Assuntos
Infecções por HIV , Infecções Sexualmente Transmissíveis , Adolescente , Humanos , Feminino , Coito , Estudos Prospectivos , Quênia , Interleucina-2 , Comportamento Sexual , Fatores ImunológicosRESUMO
BACKGROUND: For couples affected by HIV, and serodifferent couples in particular, pregnancy desire is often juxtaposed against the risk of HIV transmission between the couple and the potential neonate leading to thinking about measures to minimize risk of HIV transmission. We assess the use of fertility awareness methods [FAM] and evaluate the drivers of alignment between indicators of fertility and sexual behavior among HIV-serodifferent couples desiring pregnancy. METHODS: HIV-serodifferent couples from Thika, Kenya were enrolled into an open-label pilot evaluation of safer conception strategies. Women responded to daily 7-item short message service [SMS] surveys on FAM and sexual activity. Menstrual cycles were categorized as having condomless sex aligned, not aligned, or partially aligned to the predicted peak fertility. We used binomial logit models with generalized estimating equations to assess alignment between condomless sex during peak fertility days and FAM results. We used Cox proportional hazards to compare pregnancy incidence among months with sex and peak fertility aligned and mis-aligned. RESULTS: A total of 6929 SMS surveys across 252 menstrual cycles of 65 women were included. Reporting "sticky" cervical mucus (adjusted odds ratio [aOR]: 2.25, 95% confidence interval [95% CI]: 1.30, 3.90) and positive ovulation prediction kit [OPK] result (aOR: 2.07, 95% CI: 1.11, 3.86) were associated with increased likelihood of alignment of condomless sex during peak fertility. Pregnancy incidence was statistically similar among periods with sex aligned and not aligned with peak fertility. CONCLUSIONS: Among women engaged in a comprehensive safer conception program, a moderate percentage of women aligned condomless sex and predicted peak fertility days at least once. While FAM, particularly cervical mucus and OPK, are an inexpensive option for couples to consider using as a component of their safer conception strategies, antiretroviral-based strategies remain important to minimize risk.
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Fertilidade , Fertilização , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Adulto , Serviços de Planejamento Familiar , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Humanos , Recém-Nascido , Quênia/epidemiologia , Gravidez , Comportamento de Redução do Risco , Parceiros SexuaisRESUMO
Adolescent girls and young women (AGYW) are at high risk of HIV and other sexually transmitted infections (STIs), including at first sexual intercourse. The literature is scarce on factors influencing use of protective strategies at this critical time. We conducted 20 in-depth interviews and five focus group discussions with purposively sampled AGYW aged 16-20 years who reported first sex while enrolled in a larger cohort study and willing to participate. All AGYW were counseled on HIV prevention and had access to reproductive health information and services. Data collected were transcribed, translated and analyzed thematically. We identified two approaches to first sex. In one approach, the AGYW facilitated protection use, and those AGYW reported intention and preparation to initiate sexual activity and ability to request condom use, as well as their male partner's willingness to use and provide condoms. In another approach, AGYW experienced first sexual intercourse without agency (the feeling of control over actions and their consequences [Moore, 2016]) and described lack of prior intentions and planning, discomfort with discussions about sex and condom use, and desire to experience sexual pleasure as reported by peers. No AGYW mentioned parents/adults as playing any role as facilitators of protection use at first sex, highlighting the need for further research on the missing gap. The AGYW were trusting of verbal reports by male partners describing themselves as having never engaged in sex, HIV negative, and free of STIs. We found that some AGYW were empowered to plan, discuss, and request protection at first sex, and others did not take agency. First sex is a time of vulnerability where innovative strategies are needed to strengthen AGYW's agency and promote condom use and other HIV/STI prevention methods.
Assuntos
Coito/psicologia , Preservativos/estatística & dados numéricos , Sexo Seguro/psicologia , Adolescente , Adulto , Estudos de Coortes , Feminino , Humanos , Quênia , Masculino , Estudos Prospectivos , Adulto JovemAssuntos
Fármacos Anti-HIV/administração & dosagem , Técnicas de Laboratório Clínico/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Profilaxia Pré-Exposição/normas , Doenças Bacterianas Sexualmente Transmissíveis/diagnóstico , Adolescente , Técnicas de Laboratório Clínico/normas , Feminino , Humanos , Quênia , Profilaxia Pré-Exposição/métodos , Pesquisa Qualitativa , Adulto JovemRESUMO
Objectives: Globally, the highest rates of sexually transmitted infections (STIs) are among the 15-24 age group. Studying adolescent girls and young women (AGYW) pre-sexual debut could identify risk factors for STI acquisition. Methods: We recruited a prospective cohort of low-risk AGYW aged 16-20 in Kenya. Participants were HIV and HSV-2 seronegative and reported no history of sexual intercourse or reported sex with one partner. Participants underwent genital exams, nucleic acid testing of vaginal swabs for Neisseria gonorrhea (NG), Chlamydia trachomatis (CT), Trichomonas vaginalis (TV), and vaginal gram stains for vaginal dysbiosis by Nugent score. STI correlates were described using χ2 test and t-test. Results: We enrolled 400 AGYW, of which 322 (80.5%) reported never having had sex, while 78 (19.5%) reported prior sex with 1 partner. Among the 78 participants reporting prior sex, 20 (25.6%) reported contraception use in the last 3 months, with 60% using only emergency contraceptive pills. Despite self-reported history, of 373 subjects who underwent STI testing, 49 subjects (13.1%) tested positive for STIs, with 41 CT, 5 GC, and 3 TV cases. Of these 49 subjects, 33 (67.3%) reported no prior sexual intercourse. Bacterial vaginosis was rare and 90% of subjects had a normal Nugent score (0-3). Conclusions: Upon baseline evaluation of a cohort of low risk AGYW, we found high numbers of STIs, especially CT, which is not routinely screened for in Kenyan settings. Interventions to address STIs and unintended pregnancy should target girls pre-sexual debut, including those who do not self-identify as at risk.