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1.
PLoS One ; 16(7): e0255124, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34329334

RESUMEN

OBJECTIVE: A screening centre in Soweto, South Africa (SA), investigated high-risk human papillomavirus (HR-HPV), HIV, cervical cancer risk amongst women. METHODS: This cross-sectional study (June 2018-March 2019) describes screening results (Roche Linear Array HPV test and Pap smear liquid based cytology) and history of screening (known HIV status, antiretroviral therapy [ART] use, previous Pap smears). Data were stratified by age group (18-29, 30+ years), HIV status, Pap smear results and tested for statistical significance. RESULTS: Of 280 women, 20.4% were HIV-positive, 18.2% had abnormal Pap smears, 41.8% had HR-HPV. Of older women, 48.2% (n = 78/162) had never had a Pap smear. Of younger women, 89.0% (n = 105/118) never had a Pap smear, but had significantly more low-grade squamous intraepithelial lesions (LSIL) and other HR-HPV infection than older women (12.7%[n = 15/118] vs 4.9%[n = 8/162], p = 0.0193; and 49.2%[n = 58/118] vs 29.0%[n = 47/162], p = 0.0006; respectively). HIV-positive women had more abnormal cytology results and infection with other HR-HPV types or co-infection with other HR-HPV type(s)/HPV-16 compared to HIV-negative women (35.1%[n = 20/57] vs 13.9%[n = 31/223], p = 0.0002; 56.1%[n = 32/57] vs 32.7%[n = 73/223], p = 0.001; and 12.3%[n = 7/57] vs 4.9%[n = 11/223], p = 0.044; respectively). Of 57 HIV-positive women, 45.6% (n = 26) already knew their HIV status; of which 69.2% were on ART and 34.6% never had a Pap smear. CONCLUSION: South African women have high rates of HIV, Pap smear abnormalities and HR-HPV, with low cervical cancer screening coverage. SA cervical cancer screening policy excludes (undiagnosed) HIV-positive and HIV-negative women <30 years, both populations found to have high prevalence of HR-HPV. HPV-based primary screening from 25 years could improve outcomes.


Asunto(s)
Detección Precoz del Cáncer , Infecciones por VIH/diagnóstico , Prueba de VIH , Prueba de Papanicolaou , Infecciones por Papillomavirus/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Frotis Vaginal , Adulto , Femenino , Infecciones por VIH/epidemiología , Humanos , Infecciones por Papillomavirus/epidemiología , Guías de Práctica Clínica como Asunto , Sudáfrica/epidemiología , Neoplasias del Cuello Uterino/epidemiología
2.
PLoS One ; 15(10): e0241014, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33091093

RESUMEN

INTRODUCTION: South Africa is the HIV epidemic epicentre; however, non-communicable diseases (NCDs) will be the most common cause of death by 2030. To improve identification and initiation of care for HIV and NCDs, we assessed proportion of clients referred and linked to care (LTC) for abnormal/positive screening results and time to LTC and treatment initiation from a HIV Testing Services (HTS) Centre before and after integrated testing for NCDs with optional peer-navigated linkage to care. MATERIALS AND METHODS: This two-phase prospective study was conducted at an adult HTS Centre in Soweto, South Africa. Phase 1 (February-June 2018) utilised standard of care (SOC) HTS services (blood pressure [BP], HIV rapid diagnostic testing (RDT), sexually transmitted infections [STI]/Tuberculosis [TB] symptom screening) with passive referral for abnormal/positive results. Phase 2 (June 2018-March 2019) further integrated blood glucose/cholesterol/chlamydia RDT, with optional peer-navigated referral. Enrolled referred clients completed telephonic follow-up surveys confirming LTC/treatment initiation ≤3 months post-screening. Socio-demographics, screening results, time to LTC/treatment initiation, peer-navigated referral uptake were reported. Analysis included Fisher's exact, chi-squared, Kruskal Wallis, and Student's T-tests. Thematic analysis was conducted for open-ended survey responses. RESULTS: Of all 320 referrals, 40.0% were HIV-infections, 11.9% STIs, 6.6% TB, and 28.8% high/low BP. Of Phase 2-only referrals, 29.4% were for glucose and 23.5% cholesterol. Integrated NCD-HTS had significantly more clients LTC for HIV (76.7%[n = 66/86] vs 52.4%[n = 22/42], p = 0.0052) and within a shorter average time (6-8 days [Interquartile range (IQR):1-18.5] vs 8-13 days [IQR:2-32]) as compared to SOC HTS. Integrated NCD-HTS clients initiated HIV/STIs/BP treatment on average more quickly as compared to SOC HTS (5 days for STIs [IQR:1-21], 8 days for HIV/BP [IQR:5-17 and 2-13, respectively] vs 10 days for STIs [IQR: 4-32], 19.5 days for HIV [IQR:6.5-26.5], 8 days for BP [IQR:2-29)]. Participants chose passive over active referral (89.1% vs 10.9%; p<0.0001). Participants rejecting peer-navigated referral preferred to go alone (55.7% [n = 39/70]). Non-LTC was due to being busy (41.1% [n = 39/95]) and not being ready/refusing treatment (31.6% [n = 30/95]). Normalised results assessed at referral clinic (49.7% [n = 98/196]), prescribed lifestyle modification/monitoring (30.9% [n = 61/196]), and poor clinic flow/congestion and/or further testing required (10.7% [n = 21/196]) were associated with non-treatment initiation. CONCLUSION: Same-day treatment initiation is not achieved across diseases, despite peer-navigated referral. There are psychosocial and health systems barriers at entry to care/treatment initiation. Additional research may identify best strategies for rapid treatment initiation.


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , Enfermedades no Transmisibles/tratamiento farmacológico , Adulto , Estudios Transversales , Femenino , Prueba de VIH/métodos , Humanos , Masculino , Tamizaje Masivo/métodos , Estudios Prospectivos , Sudáfrica , Tuberculosis/tratamiento farmacológico , Trabajo
3.
BMC Health Serv Res ; 20(1): 404, 2020 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-32393224

RESUMEN

BACKGROUND: While HIV Testing Services (HTS) have increased, many South Africans have not been tested. Non-communicable diseases (NCDs) are the top cause of death worldwide. Integrated NCD-HTS could be a strategy to control both epidemics. Healthcare service strategies depends partially on positive user experience. We investigated client satisfaction of services and clinic flow time of an integrated NCD-HTS clinic. METHODS: This prospective, cross-sectional study evaluated HTS client satisfaction with an HTS clinic at two phases. Phase 1 (February-June 2018) utilised standard HTS services: counsellor-led height/weight/blood pressure measurements, HIV rapid testing, and symptoms screening for sexually transmitted infections/Tuberculosis. Phase 2 (June 2018-March 2019) further integrated counsellor-led obesity screening (body mass index/abdominal circumference measurements), rapid cholesterol/glucose testing; and nurse-led Chlamydia and human papilloma virus (HPV)/cervical cancer screening. Socio-demographics, proportion of repeat clients, clinic flow time, and client survey data (open/closed-ended questions using five-point Likert scale) are reported. Fisher's exact test, chi-square analysis, and Kruskal Wallis test conducted comparisons. Multiple linear regression determined predictors associated with clinic time. Content thematic analysis was conducted for free response data. RESULTS: Two hundred eighty-four and three hundred thirty-three participants were from Phase 1 and 2, respectively (N = 617). Phase 1 participants were significantly older (median age 36.5 (28.0-43.0) years vs. 31.0 (25.0-40.0) years; p = 0.0003), divorced/widowed (6.7%, [n = 19/282] vs. 2.4%, [n = 8/332]; p = 0.0091); had tertiary education (27.9%, [n = 79/283] vs. 20.1%, [n = 67/333]; p = 0.0234); and less female (53.9%, [n = 153/284] vs 67.6%, [n = 225/333]; p = 0.0005), compared to Phase 2. Phase 2 had 10.2% repeat clients (n = 34/333), and 97.9% (n = 320/327) were 'very satisfied' with integrated NCD-HTS, despite standard HTS having significantly shorter median time for counsellor-led HTS (36.5, interquartile range [IQR]: 31.0-45.0 vs. 41.5, IQR: 35.0-51.0; p < 0.0001). Phase 2 associations with longer clinic time were clients living together/married (est = 6.548; p = 0.0467), more tests conducted (est = 3.922; p < 0.0001), higher overall satisfaction score (est = 1.210; p = 0.0201). Those who matriculated experienced less clinic time (est = - 7.250; p = 0.0253). CONCLUSIONS: It is possible to integrate counsellor-led NCD rapid testing into standard HTS within historical HTS timeframes, yielding client satisfaction. Rapid cholesterol/glucose testing should be integrated into standard HTS. Research is required on the impact of cervical cancer/HPV screenings to HTS clinic flow to determine if it could be scaled up within the public sector.


Asunto(s)
Instituciones de Atención Ambulatoria/normas , Infecciones por VIH/diagnóstico , Satisfacción del Paciente/estadística & datos numéricos , Adolescente , Adulto , Consejo , Estudios Transversales , Femenino , Humanos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Enfermedades no Transmisibles , Aceptación de la Atención de Salud , Estudios Prospectivos , Sector Público , Sudáfrica , Adulto Joven
4.
Sci Transl Med ; 11(510)2019 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-31534016

RESUMEN

One of the most successful HIV vaccines to date, the RV144 vaccine tested in Thailand, demonstrated correlates of protection including cross-clade V1V2 immunoglobulin G (IgG) breadth, Env-specific CD4+ T cell polyfunctionality, and antibody-dependent cellular cytotoxicity (ADCC) in vaccinees with low IgA binding. The HIV Vaccine Trials Network (HVTN) 097 trial evaluated this vaccine regimen in South Africa, where clade C HIV-1 predominates. We compared cellular and humoral responses at peak and durability immunogenicity time points in HVTN 097 and RV144 vaccinee samples, and evaluated vaccine-matched and cross-clade immune responses. At peak immunogenicity, HVTN 097 vaccinees exhibited significantly higher cellular and humoral immune responses than RV144 vaccinees. CD4+ T cell responses were more frequent in HVTN 097 irrespective of age and sex, and CD4+ T cell Env-specific functionality scores were higher in HVTN 097. Env-specific CD40L+ CD4+ T cells were more common in HVTN 097, with individuals having this pattern of expression demonstrating higher median antibody responses to HIV-1 Env. IgG and IgG3 binding antibody rates and response magnitude to gp120 vaccine- and V1V2 vaccine-matched antigens were higher or comparable in HVTN 097 than in RV144 ADCC, and ADCP functional antibody responses were elicited in HVTN 097. Env-specific IgG and CD4+ Env responses declined significantly over time in both trials. Overall, cross-clade immune responses associated with protection were better than expected in South Africa, suggesting wider applicability of this regimen.


Asunto(s)
Vacunas contra el SIDA/inmunología , Adulto , Formación de Anticuerpos/inmunología , Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Ligando de CD40/metabolismo , Femenino , Anticuerpos Anti-VIH/inmunología , Antígenos VIH/inmunología , Humanos , Inmunidad Humoral , Inmunoglobulina G/inmunología , Interferón gamma/metabolismo , Interleucina-2/metabolismo , Masculino , Pruebas de Neutralización , Fagocitosis , Placebos , Análisis de Componente Principal , Sudáfrica , Linfocitos T/inmunología , Tailandia , Vacunación , Adulto Joven
5.
Drug Alcohol Depend ; 198: 192-198, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30953938

RESUMEN

BACKGROUND: South Africa has the highest number of people living with HIV (PLWH) and one of the largest antiretroviral therapy (ART) programs globally. High rates of substance use comorbidity exist, including speculation of recreational ART use (i.e., mixing ART with other illicit drugs). Recreational ART use may affect viral load among PLWH due to ART nonadherence and/or viral resistance; however, prior quantitative research has not examined rates of recreational ART use, nor associations with HIV treatment outcomes longitudinally. METHODS: Data were drawn from a prospective, observational cohort study (n = 500) of ART-eligible adults recruited from two HIV voluntary counseling and testing centers in Cape Town, and Johannesburg, South Africa. Multiple logistic regression models assessed recreational ART use as a predictor of ART initiation over six months and viral load suppression over nine months, above and beyond other substance use (binge drinking and illicit drug use). RESULTS: Approximately 5% (n = 24) reported recreational ART use, which was less frequent in Cape Town compared to Johannesburg (AOR = 0.025; 95%CI: 0.003-0.19; p < 0.001). Recreational ART use was not significantly associated with ART initiation or viral suppression. Other substance use, but not recreational ART use, was significantly associated with lower odds of ART initiation (AOR = 0.54; 95%CI: 0.33-0.87; p = .01) and viral suppression (AOR = 0.47; 95%CI: 0.25-0.89; p = .02). CONCLUSIONS: Recreational ART use was infrequent and not uniquely associated with ART initiation or viral suppression. Findings suggest that comorbid use of other substances is ultimately what may make recreational ART use problematic for ongoing engagement in care and viral suppression.


Asunto(s)
Antirretrovirales/administración & dosificación , Infecciones por VIH/tratamiento farmacológico , VIH/efectos de los fármacos , Mal Uso de Medicamentos de Venta con Receta/efectos adversos , Trastornos Relacionados con Sustancias/virología , Adolescente , Adulto , Consejo , Femenino , Infecciones por VIH/psicología , Infecciones por VIH/virología , Humanos , Modelos Logísticos , Estudios Longitudinales , Masculino , Estudios Prospectivos , Sudáfrica , Carga Viral
6.
PLoS One ; 12(7): e0180645, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28686654

RESUMEN

INTRODUCTION: The current World Health Organization guideline for first line antiretroviral therapy (ART) in HIV-infected children recommends the use of abacavir and lamivudine as nucleoside backbones and no longer includes stavudine. We compared treatment outcomes with abacavir (ABC) versus stavudine (d4T) in a cohort of HIV-1 infected children 6 and 12 months after antiretroviral therapy was initiated. METHODS: This was a retrospective case-cohort study, using programmatic data from children enrolled in the Paediatric Wellness Programme at the Perinatal HIV Research Unit in Soweto, South Africa between 2005 and 2013. Children on abacavir/stavudine who had initiated ART at age <3 years with a regimen including lamivudine and lopinavir/ritonavir and had at least one 6 or 12 month viral load result were eligible. All ABC cases identified were matched for age at ART initiation and gender to eligible d4T controls (1:2). Outcomes analysed at 6 and 12 months post ART initiation included virological failure, mortality, immunological failure and anthropometry. Chi-square tests compared categorical measures while Kruskal-Wallis compared continuous measures. RESULTS: We identified 57 eligible ABC cases and selected 114 matched d4T controls. Overall, 57% were females and 89% started treatment at age <1year. The median age at ART initiation was 3.11 (IQR: 1.98-6.05) months. There was no difference in the proportion of children virologically suppressed between the groups at 6 (ABC 54.5% vs. d4T 67.0%, p = 0.125) and 12 (ABC 66.7% vs. d4T 71.6%, p = 0.53) months post ART-initiation. The proportion of children with adherence levels >90% for ABC and d4T were similar too (95% in ABC vs. 86% in d4T, p = 0.10). The proportion of children who died over 12 months was 3.5% in the ABC and 7.9% in the d4T group (p = 0.27). Similarly, the anthropometric measures were comparable. CONCLUSIONS: It is reassuring that in the short term, in this group of patients, the treatment outcomes were similar.


Asunto(s)
Didesoxinucleósidos/administración & dosificación , Infecciones por VIH/tratamiento farmacológico , VIH/efectos de los fármacos , Estavudina/administración & dosificación , Preescolar , Combinación de Medicamentos , Femenino , VIH/patogenicidad , Infecciones por VIH/epidemiología , Infecciones por VIH/patología , Infecciones por VIH/virología , Humanos , Lactante , Lamivudine/administración & dosificación , Lopinavir/administración & dosificación , Masculino , Estudios Retrospectivos , Ritonavir/administración & dosificación , Sudáfrica/epidemiología , Resultado del Tratamiento , Carga Viral/efectos de los fármacos
7.
Curr Opin Virol ; 17: 104-109, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-26985884

RESUMEN

Novel strategies are being researched to discover vaccines to prevent and treat HIV-1. Non-efficacious preventative vaccine approaches include bivalent recombinant gp120 alone, HIV gene insertion into an Adenovirus 5 (Ad5) virus vector and the DNA prime/Ad5 boost vaccine regimen. However, the ALVAC-HIV prime/AIDSVAX® B/E gp120 boost regimen showed 31.2% efficacy at 3.5 years, and is being investigated as clade C constructs with an additional boost. Likewise, although multiple therapeutic vaccines have failed in the past, in a non-placebo controlled trial, a Tat vaccine demonstrated immune cell restoration, reduction of immune activation, and reduced HIV-1 DNA viral load. Monoclonal antibodies for passive immunization or treatment show promise, with VRC01 entering advanced clinical trials.


Asunto(s)
Vacunas contra el SIDA/inmunología , Infecciones por VIH/prevención & control , Infecciones por VIH/terapia , VIH/inmunología , Vacunas de ADN/inmunología , Vacunas contra el SIDA/administración & dosificación , Vacunas contra el SIDA/genética , Vacunas contra el SIDA/uso terapéutico , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/uso terapéutico , Ensayos Clínicos como Asunto , Vectores Genéticos , VIH/genética , Proteína gp120 de Envoltorio del VIH/genética , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/virología , Humanos , Inmunización Pasiva , Vacunación , Vacunas de ADN/genética , Vacunas de ADN/uso terapéutico , Carga Viral , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/inmunología
8.
PLoS One ; 10(9): e0136626, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26332672

RESUMEN

BACKGROUND: Three phase 2b, double-blind, placebo-controlled, randomized efficacy trials have tested recombinant Adenovirus serotype-5 (rAd5)-vector preventive HIV-1 vaccines: MRKAd5 HIV-1 gag/pol/nef in Step and Phambili, and DNA/rAd5 HIV-1 env/gag/pol in HVTN505. Due to efficacy futility observed at the first interim analysis in Step and HVTN505, participants of all three studies were unblinded to their vaccination assignments during the study but continued follow-up. Rigorous meta-analysis can provide crucial information to advise the future utility of rAd5-vector vaccines. METHODS: We included participant-level data from all three efficacy trials, and three Phase 1-2 trials evaluating the HVTN505 vaccine regimen. We predefined two co-primary analysis cohorts for assessing the vaccine effect on HIV-1 acquisition. The modified-intention-to-treat (MITT) cohort included all randomly assigned participants HIV-1 uninfected at study entry, who received at least the first vaccine/placebo, and the Ad5 cohort included MITT participants who received at least one dose of rAd5-HIV vaccine or rAd5-placebo. Multivariable Cox regression models were used to estimate hazard ratios (HRs) of HIV-1 infection (vaccine vs. placebo) and evaluate HR variation across vaccine regimens, time since vaccination, and subgroups using interaction tests. FINDINGS: Results are similar for the MITT and Ad5 cohorts; we summarize MITT cohort results. Pooled across the efficacy trials, over all follow-up time 403 (n = 224 vaccine; n = 179 placebo) of 6266 MITT participants acquired HIV-1, with a non-significantly higher incidence in vaccine recipients (HR 1.21, 95% CI 0.99-1.48, P = 0.06). The HRs significantly differed by vaccine regimen (interaction P = 0.03; MRKAd5 HR 1.41, 95% CI 1.11-1.78, P = 0.005 vs. DNA/rAd5 HR 0.88, 95% CI 0.61-1.26, P = 0.48). Results were similar when including the Phase 1-2 trials. Exploratory analyses based on the efficacy trials supported that the MRKAd5 vaccine-increased risk was concentrated in Ad5-positive or uncircumcised men early in follow-up, and in Ad5-negative or circumcised men later. Overall, MRKAd5 vaccine-increased risk was evident across subgroups except in circumcised Ad5-negative men (HR 0.97, 95% CI 0.58-1.63, P = 0.91); there was little evidence that the DNA/rAd5 vaccine, that was tested in this subgroup, increased risk (HR 0.88, 95% CI 0.61-1.26, P = 0.48). When restricting the analysis of Step and Phambili to follow-up time before unblinding, 114 (n = 65 vaccine; n = 49 placebo) of 3770 MITT participants acquired HIV-1, with a non-significantly higher incidence in MRKAd5 vaccine recipients (HR 1.30, 95% CI 0.89-1.14, P = 0.18). INTERPRETATION AND SIGNIFICANCE: The data support increased risk of HIV-1 infection by MRKAd5 over all follow-up time, but do not support increased risk of HIV-1 infection by DNA/rAd5. This study provides a rationale for including monitoring plans enabling detection of increased susceptibility to infection in HIV-1 at-risk populations.


Asunto(s)
Vacunas contra el SIDA/genética , Vacunas contra el SIDA/uso terapéutico , Adenovirus Humanos/genética , Infecciones por VIH/prevención & control , VIH-1/genética , Vectores Genéticos/genética , Vectores Genéticos/uso terapéutico , Infecciones por VIH/virología , Humanos , Estimación de Kaplan-Meier , Ensayos Clínicos Controlados Aleatorios como Asunto , Vacunas de ADN/genética , Vacunas de ADN/uso terapéutico , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética
9.
Pediatrics ; 136(1): e28-39, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26101366

RESUMEN

OBJECTIVES: Prophylactic vaccination of youngwomen aged 16 to 26 years with the 9-valent (6/11/16/18/31/33/45/52/58) human papillomavirus (HPV) virus-like particle (9vHPV) vaccine prevents infection and disease. We conducted a noninferiority immunogenicity study to bridge the findings in young women to girls and boys aged 9 to 15 years. METHODS: Subjects (N = 3066) received a 3-dose regimen of 9vHPV vaccine administered at day 1, month 2, and month 6. Anti-HPV serologic assays were performed at day 1 and month 7. Noninferiority required that the lower bound of 2-sided 95% confidence intervals of geometric mean titer ratios (boys:young women or girls:young women) be >0.67 for each HPV type. Systemic and injection-site adverse experiences (AEs) and serious AEs were monitored. RESULTS: At 4 weeks after dose 3, >99% of girls, boys, and young women seroconverted for each vaccine HPV type. Increases in geometric mean titers to HPV types 6/11/16/18/31/33/45/52/58 were elicited in all vaccine groups. Responses in girls and boys were noninferior to those of young women. Persistence of anti-HPV responses was demonstrated through 2.5 years after dose 3. Administration of the 9vHPV vaccine was generally well tolerated. A lower proportion of girls (81.9%) and boys (72.8%) than young women (85.4%) reported injection-site AEs, most of which were mild to moderate in intensity. CONCLUSIONS: These data support bridging the efficacy findings with 9vHPV vaccine in young women 16 to 26 years of age to girls and boys 9 to 15 years of age and implementing gender-neutral HPV vaccination programs in preadolescents and adolescents.


Asunto(s)
Alphapapillomavirus/inmunología , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/administración & dosificación , Vacunación/métodos , Adolescente , Adulto , Niño , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Salud Global , Humanos , Masculino , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Prevalencia , Estudios Retrospectivos , Adulto Joven
10.
Lancet Infect Dis ; 14(5): 388-96, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24560541

RESUMEN

BACKGROUND: The HVTN 503/Phambili study, which assessed the efficacy of the Merck Ad5 gag/pol/nef subtype B HIV-1 preventive vaccine in South Africa, was stopped when futility criteria in the Step study (assessing the same vaccine in the Americas, Caribbean, and Australia) were met. Here we report long-term follow-up data. METHODS: HVTN 503/Phambili was a double-blind, placebo-controlled, randomised trial that recruited HIV-1 uninfected, sexually active adults aged 18-35 years from five sites in South Africa. Eligible participants were randomly assigned (1:1) by computer-generated random numbers to either vaccine or placebo, stratified by site and sex. Cox proportional hazards models were used to estimate HIV-1 infection in the modified intention-to-treat cohort, all of whom were unmasked early in follow-up. The trial is registered with ClinicalTrials.gov, number NCT00413725 and the South African National Health Research Database, number DOH-27-0207-1539. FINDINGS: Between Jan 24, 2007, and Sept 19, 2007, 801 participants (26·7%) of a planned 3000 were randomly assigned (400 to vaccine, 401 to placebo); 216 (27%) received only one injection, 529 (66%) received only two injections, and 56 (7%) received three injections. At a median follow-up of 42 months (IQR 31-42), 63 vaccine recipients (16%) had HIV-1 infection compared with 37 placebo recipients (9%; adjusted HR 1·70, 95% CI 1·13-2·55; p=0·01). Risk for HIV-1 infection did not differ according to the number of vaccinations received, sex, circumcision, or adenovirus type 5 (Ad5) serostatus. Differences in risk behaviour at baseline or during the study, or annualised dropout rate (7·7% [95% CI 6·2-9·5] for vaccine recipients vs 8·8% [7·1-10·7] for placebo recipients; p=0·40) are unlikely explanations for the increased rate of HIV-1 infections seen in vaccine recipients. INTERPRETATION: The increased risk of HIV-1 acquisition in vaccine recipients, irrespective of number of doses received, warrants further investigation to understand the biological mechanism. We caution against further use of the Ad5 vector for HIV vaccines. FUNDING: National Institute of Allergy and Infectious Diseases, Merck, and South African Medical Research Council.


Asunto(s)
Vacunas contra el SIDA/administración & dosificación , Adenoviridae/genética , Vectores Genéticos , Infecciones por VIH/prevención & control , Precursores de Proteínas/inmunología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/inmunología , Adolescente , Adulto , Método Doble Ciego , Femenino , Estudios de Seguimiento , Infecciones por VIH/epidemiología , Humanos , Incidencia , Masculino , Modelos de Riesgos Proporcionales , Medición de Riesgo , Sudáfrica , Vacunas Sintéticas/inmunología , Adulto Joven
11.
J Immunol Tech Infect Dis ; 2(3)2013 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-24324979

RESUMEN

BACKGROUND: Self-sampling for Human Papillomavirus (HPV) testing may offer improved patient acceptability, decreased cost, and greater practicality than clinician collection of specimens. HPV testing among adolescents is necessary to conduct vaccine surveillance and may play a role in cervical cancer screening among some populations. METHODS: A cross-sectional prevalence study was conducted to compare the results of self-collected and clinician-collected specimens for Human papillomavirus (HPV) testing among South African adolescent females. All participants provided self-sampled vaginal swabs and underwent clinician-collection of cervical swabs for HPV DNA analysis. The level of agreement between HPV DNA results from the two specimen collection methods was measured. RESULTS: The level of agreement between HPV DNA results from self-collected and clinician-collected specimens was high (κ=86.7; p<0.001). A high prevalence of HPV overall was found by both specimen collection methods (57%; 95% CI 0.37-0.75). Low-risk HPV (LR-HPV) types were found slightly more frequently in self-collected specimens. CONCLUSION: There is a high level of agreement between the HPV DNA results from self-collected and clinician-collected specimens. Self-collection of specimens for HPV testing is a viable alternative among adolescents.

12.
PLoS One ; 8(8): e72094, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24023613

RESUMEN

BACKGROUND: In South Africa, the prevalence of oncogenic Human Papillomavirus (HPV) may be as high as 64%, and cervical cancer is the leading cause of cancer-related death among women. The development of efficacious prophylactic vaccines has provided an opportunity for primary prevention. Given the importance of psycho-social forces in vaccine uptake, we sought to elucidate factors influencing HPV vaccination among a sample of low-income South African adolescents receiving the vaccine for the first time in Soweto. METHODS: The HPV vaccine was introduced to adolescents in low-income townships throughout South Africa as part of a nationwide trial to understand adolescent involvement in future vaccine research targeting human immunodeficiency virus (HIV). We performed in-depth semi-structured interviews with purposively-sampled adolescents and their care providers to understand what forces shaped HPV vaccine uptake. Interviews were recorded, transcribed, translated, and examined using thematic analysis. RESULTS: Of 224 adolescents recruited, 201 initiated the vaccine; 192 (95.5%) received a second immunization; and 164 (81.6%) completed three doses. In our qualitative study of 39 adolescent-caregiver dyads, we found that factors driving vaccine uptake reflected a socio-cultural backdrop of high HIV endemnicity, sexual violence, poverty, and an abundance of female-headed households. Adolescents exercised a high level of autonomy and often initiated decision-making. Healthcare providers and peers provided support and guidance that was absent at home. The impact of the HIV epidemic on decision-making was substantial, leading participants to mistakenly conflate HPV and HIV. CONCLUSIONS: In a setting of perceived rampant sexual violence and epidemic levels of HIV, adolescents and caregivers sought to decrease harm by seeking a vaccine targeting a sexually transmitted infection (STI). Despite careful consenting, there was confusion regarding the vaccine's target. Future interventions promoting STI vaccines will need to provide substantial information for participants, particularly adolescents who may exercise a significant level of autonomy in decision-making.


Asunto(s)
Cuidadores/estadística & datos numéricos , Vacunas contra Papillomavirus/administración & dosificación , Investigación Cualitativa , Adolescente , Niño , Toma de Decisiones , Composición Familiar , Femenino , Infecciones por VIH/epidemiología , Reducción del Daño , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Delitos Sexuales , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/inmunología , Enfermedades de Transmisión Sexual/prevención & control , Enfermedades de Transmisión Sexual/virología , Sudáfrica/epidemiología , Adulto Joven
13.
Vaccine ; 29(32): 5203-9, 2011 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-21619905

RESUMEN

Recombinant adenovirus serotype 5 (rAd5) vaccine vectors for HIV-1 and other pathogens have been shown to be limited by high titers of Ad5 neutralizing antibodies (NAbs) in the developing world. Alternative serotype rAd vectors have therefore been constructed. Here we report Ad5, Ad26, Ad35, and Ad48 NAb titers in 4381 individuals from North America, South America, sub-Saharan Africa, and Southeast Asia. As expected, Ad5 NAb titers were both frequent and high magnitude in sub-Saharan Africa and Southeast Asia. In contrast, Ad35 NAb titers proved infrequent and low in all regions studied, and Ad48 NAbs were rare in all regions except East Africa. Ad26 NAbs were moderately common in adults in sub-Saharan Africa and Southeast Asia, but Ad26 NAb titers proved markedly lower than Ad5 NAb titers in all regions, and these relatively low Ad26 NAb titers did not detectably suppress the immunogenicity of 4×10(10)vp of a rAd26-Gag/Pol/Env/Nef vaccine in rhesus monkeys. These data inform the clinical development of alternative serotype rAd vaccine vectors in the developing world.


Asunto(s)
Infecciones por Adenoviridae/epidemiología , Infecciones por Adenoviridae/inmunología , Adenoviridae/inmunología , Anticuerpos Antivirales/inmunología , Vacunas Virales/inmunología , Vacunas contra el SIDA/inmunología , Adenoviridae/aislamiento & purificación , Infecciones por Adenoviridae/sangre , Infecciones por Adenoviridae/virología , Adolescente , Adulto , Animales , Anticuerpos Antivirales/sangre , Niño , VIH-1/inmunología , Humanos , Lactante , Macaca mulatta/inmunología , Vacunas Sintéticas/inmunología , Adulto Joven
14.
Lancet Infect Dis ; 11(7): 507-15, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21570355

RESUMEN

BACKGROUND: The MRKAd5 HIV-1 gag/pol/nef subtype B vaccine was designed to elicit T-cell-mediated immune responses capable of providing complete or partial protection from HIV-1 infection or a decrease in viral load after acquisition. We aim to assess the safety and efficacy of the vaccine in South Africa, where the major circulating clade is subtype C. METHODS: We did a phase 2b double-blind, randomised test-of-concept study in sexually active HIV-1 seronegative participants at five sites in South Africa. Randomisation was by a computer-generated random number sequence. The vaccine and placebo were given by intramuscular injection on a 0, 1, 6 month schedule. Our coprimary endpoints were a vaccine-induced reduction in HIV-1 acquisition and viral-load setpoint. These endpoints were assessed independently in the modified intention-to-treat (MITT) cohort with two-tailed significance tests stratified by sex. We assessed immunogenicity by interferon-γ ELISPOT in peripheral-blood mononuclear cells. After the lack of efficacy of the MRKAd5 HIV-1 vaccine in the Step study, enrolment and vaccination in our study was halted, treatment allocations were unmasked, and follow-up continued. This study is registered with the South Africa National Health Research Database, number DOH-27-0207-1539, and ClinicalTrials.gov, number NCT00413725. FINDINGS: 801 of a scheduled 3000 participants, of whom 360 (45%) were women, were randomly assigned to receive either vaccine or placebo. 445 participants (56%) had adenovirus serotype 5 (Ad5) titres greater than 200, and 129 men (29%) were circumcised. 34 MITT participants in the vaccine group were diagnosed with HIV-1 (incidence rate 4·54 per 100 person-years) and 28 in the placebo group (3·70 per 100 person-years). There was no evidence of vaccine efficacy; the hazard ratio adjusted for sex was 1·25 (95% CI 0·76-2·05). Vaccine efficacy did not differ by Ad5 titre, sex, age, herpes simplex virus type 2 status, or circumcision. The geometric mean viral-load setpoint was 20,483 copies per mL (n=33) in the vaccine group and 34,032 copies per mL (n=28) in the placebo group (p=0·39). The vaccine elicited interferon-γ-secreting T cells that recognised both clade B (89%) and C (77%) antigens. INTERPRETATION: The MRKAd5 HIV-1 vaccine did not prevent HIV-1 infection or lower viral-load setpoint; however, stopping our trial early probably compromised our ability to draw conclusions. The high incidence rates noted in South Africa highlight the crucial need for intensified efforts to develop an efficacious vaccine. FUNDING: The US National Institute of Allergy and Infectious Disease and Merck and Co Inc.


Asunto(s)
Vacunas contra el SIDA/administración & dosificación , Infecciones por VIH/prevención & control , VIH-1/inmunología , Vacunas contra el SIDA/efectos adversos , Vacunas contra el SIDA/inmunología , Adolescente , Adulto , Estudios de Cohortes , Método Doble Ciego , Femenino , Infecciones por VIH/inmunología , Humanos , Inmunidad Celular/inmunología , Interferón gamma/sangre , Masculino , Modelos de Riesgos Proporcionales , ARN Viral/sangre , Sudáfrica , Adulto Joven
15.
AIDS ; 25(1): 87-94, 2011 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-21076276

RESUMEN

OBJECTIVE: To ascertain progression and regression of cervical dysplasia in HIV-infected women in Soweto. DESIGN: Prospective cohort. METHODS: Women attending an HIV wellness clinic were offered cervical smears as part of care; smears were assessed using the Bethesda system. Those with high-grade lesions or worse were referred for colposcopy. Progression analyses included women with at least two smears at least 5.5 months apart. Hazard ratios were used to ascertain predictors of progression. RESULTS: Two thousand, three hundred and twenty-five women had a baseline smear; their median age and CD4 cell count was 32 years and 312 cells/µl, respectively; 17% were taking highly active antiretroviral therapy (HAART); 62, 20 and 14% had normal, low-grade squamous intraepithelial lesions (LSIL) or high-grade squamous intraepithelial lesions (HSIL), respectively. Of those with baseline normal or LSIL smears, 1074 had another smear; progression from normal to LSIL was 9.6/100 person-years (95% CI 8.3-11.1) and progression from normal or LSIL to HSIL was 4.6/100 person-years (95% CI 3.9-5.5). Of 225 women with LSIL at baseline and at least one subsequent smear at least 11.5 months later, 44.0% regressed to normal (21.2/100 person-years (95% CI 17.5-25.7)). Multivariate models suggested increasing risk for progression in women with CD4 cell count below 500 cells/µl and HAART may reduce the risk of progression [adjusted hazard ratio (aHR) 0.72 (0.52-0.99)]. CONCLUSION: HIV-infected women have high rates of prevalent and incident HSIL and LSIL with relatively low risk of regression to normal from LSIL. HAART appears to protect against progression. Our findings suggest cervical screening intervals should be less than 10 years - irrespective of age in women with CD4 cell counts below 500 cells/µl.


Asunto(s)
Infecciones por VIH/complicaciones , VIH-1/aislamiento & purificación , Displasia del Cuello del Útero/diagnóstico , Neoplasias del Cuello Uterino/patología , Adulto , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Humanos , Lesiones Precancerosas/diagnóstico , Estudios Prospectivos , ARN Viral , Factores de Riesgo , Sudáfrica/epidemiología , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/virología , Frotis Vaginal/estadística & datos numéricos , Displasia del Cuello del Útero/epidemiología , Displasia del Cuello del Útero/virología
16.
Expert Rev Anti Infect Ther ; 8(1): 23-31, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20014899

RESUMEN

The demonstration of a strong effect of male circumcision on reducing HIV acquisition has provided impetus for this intervention to be adopted more widely in areas of the world where HIV prevalence is high and rates of male circumcision are low. This perspective reviews recent research findings and provides a summary of progress in various countries.


Asunto(s)
Circuncisión Masculina , Infecciones por VIH/prevención & control , África del Sur del Sahara , Circuncisión Masculina/efectos adversos , Infecciones por VIH/psicología , Infecciones por VIH/transmisión , Herpes Genital/prevención & control , Humanos , Masculino , Infecciones por Papillomavirus/prevención & control , Enfermedades de Transmisión Sexual/prevención & control , Enfermedades de Transmisión Sexual/transmisión
18.
J Virol Methods ; 144(1-2): 115-21, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17543395

RESUMEN

A whole blood peptide mapping intracellular cytokine staining (ICS) assay was developed that allows the direct comparison, at the individual peptide level, of CD4(+) and CD8(+) T-cell responses that span every encoded protein, in patients infected with HIV-1. Whole blood samples from HIV-1 infected patients were stimulated with overlapping synthetic peptides spanning nine subtype C HIV-1 gene regions (Gag, Pol, Nef, Env, Tat, Rev, Vif, Vpu, Vpr). Following stimulation and permeabilization, cells were stained with fluorochrome labelled antibodies to CD3, CD8 (CD4(+) cells were defined as CD8 negative cells), and IL-2 and IFN-gamma. A total of 396 overlapping peptides were arranged in pools with a matrix design which allowed the identification of individual peptide responses from multiple pool responses. HIV-1 infected patients screened using this method showed a broad range of peptide responses across the entire HIV-1 genome with CD8 T-cell responses being higher in frequency in magnitude than CD4(+) T-cell responses. The advantages of this whole blood ICS assay include the following: (1) the response to all potential HIV-1 epitopes across the genome can be examined, (2) the responding cell type can be monitored in the same reaction, and (3) considerably less blood is required than would be necessary if peripheral blood mononuclear cells (PBMC) were first isolated prior to peptide stimulation.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Citocinas/sangre , Técnica del Anticuerpo Fluorescente Directa/métodos , Antígenos VIH/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Citocinas/inmunología , Citocinas/metabolismo , Femenino , Genoma Viral , Antígenos VIH/metabolismo , VIH-1/genética , Humanos , Péptidos/inmunología
19.
Curr Opin Mol Ther ; 9(2): 168-75, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17458171

RESUMEN

Vertical transmission, or mother-to-child transmission (MTCT), is the main mode of HIV-1 acquisition in infants and children. The presence of passively transferred maternal antibodies to HIV-1 has not protected infants front HIV-1 infection and there is no clear understanding about the role of antibodies in preventing MTCT. Immune factors, such as leukemia inhibitory factor, CC chemokines, Lewis X component and secretory leukocyte protease inhibitor, appear to be involved in the protection of HIV-exposed, uninfected infants. The mainstay of reducing HIV transmission risk in infants remains the use of antiretroviral therapy. Future strategies to augment the role of antiretrovirals in preventing MTCT, or to target the prevention of transmission through breastfeeding, may include the use of vaccination and/or passive immunization with neutralizing monoclonal antibodies.


Asunto(s)
Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , VIH-1/fisiología , Factores Inmunológicos/inmunología , Transmisión Vertical de Enfermedad Infecciosa , Madres , Terapia Antirretroviral Altamente Activa , Niño , Infecciones por VIH/tratamiento farmacológico , Humanos
20.
Clin Vaccine Immunol ; 14(4): 348-54, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17301218

RESUMEN

Human immunodeficiency virus type 1 (HIV-1)-specific cellular immune responses are elicited in a proportion of infants born to HIV-1-infected mothers and are associated with protection against vertical transmission. To investigate correlates of these HIV-1-specific responses, we examined levels of the immune activation markers neopterin, beta(2)-microglobulin (beta(2)-m), and soluble l-selectin (sl-selectin); the immunomodulatory and hematopoietic factors interleukin-7 (IL-7), stromal-cell-derived factor 1 alpha (CXCL12), and granulocyte-macrophage colony-stimulating factor (GM-CSF); and the immunoregulatory cytokine IL-10 among a group of newborns born to HIV-1-positive mothers who did not receive any antiretroviral drugs for prevention of perinatal HIV-1 transmission. Cellular immune responses to HIV-1 envelope (Env) peptides were also measured. We aimed to determine whether newborns who elicit HIV-1-specific cellular immune responses (Env(+)) and those who lack these responses (Env(-)) exhibit unique immune features. Our data confirmed that no Env(+) infants acquired HIV-1 infection. Among exposed, uninfected infants, Env(+) infants had reduced immune activation (as measured by beta(2)-m and sl-selectin levels in cord blood plasma) compared to Env(-) infants as well as reduced GM-CSF levels in cord blood plasma. There was also a reduced ability of cord blood mononuclear cells to be induced to produce GM-CSF among Env(+) infants. Maternal viral load was lower in Env(+) infants, suggesting that exposure to low levels of antigen may be responsible for priming the protective responses. These findings suggest that infants who are able to develop apparently protective HIV-1-specific cellular immune responses have immunological features and viral exposure histories that distinguish them from their nonresponder counterparts, providing new insights into the development of HIV-1 protective immunity.


Asunto(s)
Epítopos/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Antígenos VIH/inmunología , VIH-1/inmunología , Inmunidad Materno-Adquirida/inmunología , Carga Viral , Adulto , Células Cultivadas , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/antagonistas & inhibidores , Humanos , Lactante , Recién Nacido , Estudios Prospectivos
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