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1.
N Engl J Med ; 384(12): 1089-1100, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33761206

RESUMO

BACKGROUND: A safe, effective vaccine is essential to eradicating human immunodeficiency virus (HIV) infection. A canarypox-protein HIV vaccine regimen (ALVAC-HIV plus AIDSVAX B/E) showed modest efficacy in reducing infection in Thailand. An analogous regimen using HIV-1 subtype C virus showed potent humoral and cellular responses in a phase 1-2a trial in South Africa. Efficacy data and additional safety data were needed for this regimen in a larger population in South Africa. METHODS: In this phase 2b-3 trial, we randomly assigned 5404 adults without HIV-1 infection to receive the vaccine (2704 participants) or placebo (2700 participants). The vaccine regimen consisted of injections of ALVAC-HIV at months 0 and 1, followed by four booster injections of ALVAC-HIV plus bivalent subtype C gp120-MF59 adjuvant at months 3, 6, 12, and 18. The primary efficacy outcome was the occurrence of HIV-1 infection from randomization to 24 months. RESULTS: In January 2020, prespecified criteria for nonefficacy were met at an interim analysis; further vaccinations were subsequently halted. The median age of the trial participants was 24 years; 70% of the participants were women. The incidence of adverse events was similar in the vaccine and placebo groups. During the 24-month follow-up, HIV-1 infection was diagnosed in 138 participants in the vaccine group and in 133 in the placebo group (hazard ratio, 1.02; 95% confidence interval, 0.81 to 1.30; P = 0.84). CONCLUSIONS: The ALVAC-gp120 regimen did not prevent HIV-1 infection among participants in South Africa despite previous evidence of immunogenicity. (HVTN 702 ClinicalTrials.gov number, NCT02968849.).


Assuntos
Vacinas contra a AIDS , Adjuvantes Imunológicos , Infecções por HIV/prevenção & controle , HIV-1 , Imunogenicidade da Vacina , Polissorbatos , Esqualeno , Vacinas contra a AIDS/imunologia , Adolescente , Adulto , Vírus da Varíola dos Canários , Método Duplo-Cego , Feminino , Vetores Genéticos , HIV-1/genética , Humanos , Imunização Secundária , Masculino , África do Sul , Falha de Tratamento , Adulto Jovem
2.
Lancet ; 399(10330): 1141-1153, 2022 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-35305740

RESUMO

BACKGROUND: We aimed to assess the effectiveness of a single dose of the Ad26.COV2.S vaccine (Johnson & Johnson) in health-care workers in South Africa during two waves of the South African COVID-19 epidemic. METHODS: In the single-arm, open-label, phase 3B implementation Sisonke study, health-care workers aged 18 years and older were invited for vaccination at one of 122 vaccination sites nationally. Participants received a single dose of 5 × 1010 viral particles of the Ad26.COV2.S vaccine. Vaccinated participants were linked with their person-level data from one of two national medical insurance schemes (scheme A and scheme B) and matched for COVID-19 risk with an unvaccinated member of the general population. The primary outcome was vaccine effectiveness against severe COVID-19, defined as COVID-19-related admission to hospital, hospitalisation requiring critical or intensive care, or death, in health-care workers compared with the general population, ascertained 28 days or more after vaccination or matching, up to data cutoff. This study is registered with the South African National Clinical Trial Registry, DOH-27-022021-6844, ClinicalTrials.gov, NCT04838795, and the Pan African Clinical Trials Registry, PACTR202102855526180, and is closed to accrual. FINDINGS: Between Feb 17 and May 17, 2021, 477 102 health-care workers were enrolled and vaccinated, of whom 357 401 (74·9%) were female and 119 701 (25·1%) were male, with a median age of 42·0 years (33·0-51·0). 215 813 vaccinated individuals were matched with 215 813 unvaccinated individuals. As of data cutoff (July 17, 2021), vaccine effectiveness derived from the total matched cohort was 83% (95% CI 75-89) to prevent COVID-19-related deaths, 75% (69-82) to prevent COVID-19-related hospital admissions requiring critical or intensive care, and 67% (62-71) to prevent COVID-19-related hospitalisations. The vaccine effectiveness for all three outcomes were consistent across scheme A and scheme B. The vaccine effectiveness was maintained in older health-care workers and those with comorbidities including HIV infection. During the course of the study, the beta (B.1.351) and then the delta (B.1.617.2) SARS-CoV-2 variants of concerns were dominant, and vaccine effectiveness remained consistent (for scheme A plus B vaccine effectiveness against COVID-19-related hospital admission during beta wave was 62% [95% CI 42-76] and during delta wave was 67% [62-71], and vaccine effectiveness against COVID-19-related death during beta wave was 86% [57-100] and during delta wave was 82% [74-89]). INTERPRETATION: The single-dose Ad26.COV2.S vaccine shows effectiveness against severe COVID-19 disease and COVID-19-related death after vaccination, and against both beta and delta variants, providing real-world evidence for its use globally. FUNDING: National Treasury of South Africa, the National Department of Health, Solidarity Response Fund NPC, The Michael & Susan Dell Foundation, The Elma Vaccines and Immunization Foundation, and the Bill & Melinda Gates Foundation.


Assuntos
COVID-19 , Infecções por HIV , Vacinas , Ad26COVS1 , Adolescente , Adulto , Idoso , COVID-19/epidemiologia , COVID-19/prevenção & controle , Feminino , Humanos , Masculino , SARS-CoV-2 , África do Sul/epidemiologia
3.
AIDS Behav ; 27(1): 231-244, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35841462

RESUMO

Adolescent girls and young women (AGYW) living with HIV have poor antiretroviral therapy (ART) outcomes. We examined the relationship between psychosocial factors with knowledge of HIV-positive status and antiretroviral therapy exposure among AGYW living with HIV in South Africa. Participants 15-24 years responded to a survey including socio-demographics, psychosocial factors, and HIV testing. Blood was collected to determine HIV status and ART exposure. Multivariable analyses were conducted using R. Of 568 participants with HIV, 356 had knowledge of their HIV-positive status. Social support from family [aOR 1.14 (95% CI 1.04-1.24)] or from a special person [aOR 1.12 (95% CI 1.02-1.23)] was associated with knowledge of HIV-positive status. Resilience [aOR 1.05 (95% CI 1.01-1.08)] was the only psychosocial factor associated with a higher odds of ART exposure. Social support and resilience may increase knowledge of HIV-positive status and ART exposure among South African AGYW.


Assuntos
Infecções por HIV , Humanos , Feminino , Adolescente , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , África do Sul/epidemiologia , Antirretrovirais/uso terapêutico , Inquéritos e Questionários , Apoio Social
4.
AIDS Behav ; 27(9): 3027-3037, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36929319

RESUMO

In South Africa, HIV acquisition risk has been studied less in people assigned male at birth. We studied the associations between risk behaviors, clinical features and HIV incidence amongst males in two South African HIV preventive vaccine efficacy trials. We used Cox proportional hazards models to test for associations between demographics, sexual behaviors, clinical variables and HIV acquisition among males followed in the HVTN 503 (n = 219) and HVTN 702 (n = 1611) trials. Most males reported no male sexual partners (99.09% in HVTN 503) or identified as heterosexual (88.08% in HVTN 702). Annual HIV incidence was 1.39% in HVTN 503 (95% CI 0.76-2.32%) and 1.33% in HVTN 702 (95% CI 0.80-2.07%). Increased HIV acquisition was significantly associated with anal sex (HR 6.32, 95% CI 3.44-11.62), transactional sex (HR 3.42, 95% CI 1.80-6.50), and non-heterosexual identity (HR 16.23, 95%CI 8.13-32.41) in univariate analyses and non-heterosexual identity (HR 14.99, 95% CI 4.99-45.04; p < 0.01) in multivariate analysis. It is appropriate that prevention efforts in South Africa, although focused on the severe epidemic in young women, also encompass key male populations, including men who have sex with men, but also men who engage in anal or transactional sex.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , Minorias Sexuais e de Gênero , Humanos , Masculino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Fatores de Risco , Comportamento Sexual , África do Sul/epidemiologia , Eficácia de Vacinas , Ensaios Clínicos como Assunto
5.
BMC Health Serv Res ; 23(1): 753, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37443064

RESUMO

INTRODUCTION: Reliable and timely laboratory results are crucial for monitoring the Prevention of the Mother-to-Child Transmission (PMTCT) cascade, particularly to enable early HIV diagnosis and early intervention. We sought to explore whether and how laboratory services have been prepared to absorb new testing requirements following PMTCT Test-and-Treat policy changes in three districts of Zambia. METHOD: We employed in-depth interviews and thematic data analysis, informed by the health system dynamic framework. Twenty-Six health workers were purposively selected and a document review of laboratory services in the context of PMTCT was undertaken. All face-to-face interviews were conducted in three local government areas in the Copperbelt Province (one urban and two rural) between February 2019 and July 2020. We extracted notes and markings from the transcripts for coding. Different codes were sorted into potential themes and the data extracted were put within the identified themes. Trustworthiness was confirmed by keeping records of all data field notes, transcripts, and reflexive journals. RESULTS: The findings revealed that the health system inputs (infrastructure and supplies, human resources, knowledge, and information and finance) and service delivery were unequal between the rural and urban sites, and this affected the ability of health facilities to apply the new testing requirements, especially, in the rural-based health facilities. The major barriers identified include gaps in the capacity of the existing laboratory system to perform crucial PMTCT clinical and surveillance functions in a coordinated manner and insufficient skilled human resources to absorb the increased testing demands. The centralized laboratory system for HIV testing of mothers and exposed neonates meant facilities had to send specimens to other facilities and districts which resulted in high turnaround time and hence delayed HIV diagnosis. CONCLUSION: New guidelines implemented without sufficient capacitation of health system laboratory capacity severely limited the effectiveness of PMTCT program implementation. This study documented the areas relating to health system inputs and laboratory service delivery where greater support to enable the absorption of the new testing requirements is needed.


Assuntos
Infecções por HIV , Recém-Nascido , Humanos , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/prevenção & controle , Infecções por HIV/epidemiologia , Zâmbia/epidemiologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Programas Governamentais , Teste de HIV
6.
J Infect Dis ; 226(2): 246-257, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35758878

RESUMO

BACKGROUND: The ALVAC/gp120 + MF59 vaccines in the HIV Vaccine Trials Network (HVTN) 702 efficacy trial did not prevent human immunodeficiency virus-1 (HIV-1) acquisition. Vaccine-matched immunological endpoints that were correlates of HIV-1 acquisition risk in RV144 were measured in HVTN 702 and evaluated as correlates of HIV-1 acquisition. METHODS: Among 1893 HVTN 702 female vaccinees, 60 HIV-1-seropositive cases and 60 matched seronegative noncases were sampled. HIV-specific CD4+ T-cell and binding antibody responses were measured 2 weeks after fourth and fifth immunizations. Cox proportional hazards models assessed prespecified responses as predictors of HIV-1 acquisition. RESULTS: The HVTN 702 Env-specific CD4+ T-cell response rate was significantly higher than in RV144 (63% vs 40%, P = .03) with significantly lower IgG binding antibody response rate and magnitude to 1086.C V1V2 (67% vs 100%, P < .001; Pmag < .001). Although no significant univariate associations were observed between any T-cell or binding antibody response and HIV-1 acquisition, significant interactions were observed (multiplicity-adjusted P ≤.03). Among vaccinees with high IgG A244 V1V2 binding antibody responses, vaccine-matched CD4+ T-cell endpoints associated with decreased HIV-1 acquisition (estimated hazard ratios = 0.40-0.49 per 1-SD increase in CD4+ T-cell endpoint). CONCLUSIONS: HVTN 702 and RV144 had distinct immunogenicity profiles. However, both identified significant correlations (univariate or interaction) for IgG V1V2 and polyfunctional CD4+ T cells with HIV-1 acquisition. Clinical Trials Registration . NCT02968849.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , Soropositividade para HIV , HIV-1 , Feminino , Anticorpos Anti-HIV , Proteína gp120 do Envelope de HIV , Infecções por HIV/prevenção & controle , Humanos , Imunoglobulina G , Masculino , África do Sul
7.
Clin Infect Dis ; 75(1): e289-e292, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35353885

RESUMO

We report a 23% asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) Omicron carriage rate in participants being enrolled into a clinical trial in South Africa, 15-fold higher than in trials before Omicron. We also found lower CD4 + T-cell counts in persons with human immunodeficiency virus (HIV) strongly correlated with increased odds of being SARS-CoV-2 polymerase chain reaction (PCR) positive.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Reação em Cadeia da Polimerase , África do Sul/epidemiologia
8.
PLoS Med ; 17(2): e1003038, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32092060

RESUMO

BACKGROUND: HVTN 100 evaluated the safety and immunogenicity of an HIV subtype C pox-protein vaccine regimen, investigating a 12-month booster to extend vaccine-induced immune responses. METHODS AND FINDINGS: A phase 1-2 randomized double-blind placebo-controlled trial enrolled 252 participants (210 vaccine/42 placebo; median age 23 years; 43% female) between 9 February 2015 and 26 May 2015. Vaccine recipients received ALVAC-HIV (vCP2438) alone at months 0 and 1 and with bivalent subtype C gp120/MF59 at months 3, 6, and 12. Antibody (IgG, IgG3 binding, and neutralizing) and CD4+ T-cell (expressing interferon-gamma, interleukin-2, and CD40 ligand) responses were evaluated at month 6.5 for all participants and at months 12, 12.5, and 18 for a randomly selected subset. The primary analysis compared IgG binding antibody (bAb) responses and CD4+ T-cell responses to 3 vaccine-matched antigens at peak (month 6.5 versus 12.5) and durability (month 12 versus 18) timepoints; IgG responses to CaseA2_gp70_V1V2.B, a primary correlate of risk in RV144, were also compared at these same timepoints. Secondary and exploratory analyses compared IgG3 bAb responses, IgG bAb breadth scores, neutralizing antibody (nAb) responses, antibody-dependent cellular phagocytosis, CD4+ polyfunctionality responses, and CD4+ memory sub-population responses at the same timepoints. Vaccines were generally safe and well tolerated. During the study, there were 2 deaths (both in the vaccine group and both unrelated to study products). Ten participants became HIV-infected during the trial, 7% (3/42) of placebo recipients and 3% (7/210) of vaccine recipients. All 8 serious adverse events were unrelated to study products. Less waning of immune responses was seen after the fifth vaccination than after the fourth, with higher antibody and cellular response rates at month 18 than at month 12: IgG bAb response rates to 1086.C V1V2, 21.0% versus 9.7% (difference = 11.3%, 95% CI = 0.6%-22.0%, P = 0.039), and ZM96.C V1V2, 21.0% versus 6.5% (difference = 14.5%, 95% CI = 4.1%-24.9%, P = 0.004). IgG bAb response rates to all 4 primary V1V2 antigens were higher 2 weeks after the fifth vaccination than 2 weeks after the fourth vaccination: 87.7% versus 75.4% (difference = 12.3%, 95% CI = 1.7%-22.9%, P = 0.022) for 1086.C V1V2, 86.0% versus 63.2% (difference = 22.8%, 95% CI = 9.1%-36.5%, P = 0.001) for TV1c8.2.C V1V2, 67.7% versus 44.6% (difference = 23.1%, 95% CI = 10.4%-35.7%, P < 0.001) for ZM96.C V1V2, and 81.5% versus 60.0% (difference = 21.5%, 95% CI = 7.6%-35.5%, P = 0.002) for CaseA2_gp70_V1V2.B. IgG bAb response rates to the 3 primary vaccine-matched gp120 antigens were all above 90% at both peak timepoints, with no significant differences seen, except a higher response rate to ZM96.C gp120 at month 18 versus month 12: 64.5% versus 1.6% (difference = 62.9%, 95% CI = 49.3%-76.5%, P < 0.001). CD4+ T-cell response rates were higher at month 18 than month 12 for all 3 primary vaccine-matched antigens: 47.3% versus 29.1% (difference = 18.2%, 95% CI = 2.9%-33.4%, P = 0.021) for 1086.C, 61.8% versus 38.2% (difference = 23.6%, 95% CI = 9.5%-37.8%, P = 0.001) for TV1.C, and 63.6% versus 41.8% (difference = 21.8%, 95% CI = 5.1%-38.5%, P = 0.007) for ZM96.C, with no significant differences seen at the peak timepoints. Limitations were that higher doses of gp120 were not evaluated, this study was not designed to investigate HIV prevention efficacy, and the clinical significance of the observed immunological effects is uncertain. CONCLUSIONS: In this study, a 12-month booster of subtype C pox-protein vaccines restored immune responses, and slowed response decay compared to the 6-month vaccination. TRIAL REGISTRATION: ClinicalTrials.gov NCT02404311. South African National Clinical Trials Registry (SANCTR number: DOH--27-0215-4796).


Assuntos
Vacinas contra a AIDS/uso terapêutico , Anticorpos Neutralizantes/imunologia , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/prevenção & controle , Proteínas do Vírus da Imunodeficiência Humana/imunologia , Imunização Secundária , Imunoglobulina G/imunologia , Vacinas contra a AIDS/imunologia , Adulto , Artralgia/induzido quimicamente , Método Duplo-Cego , Feminino , Cefaleia/induzido quimicamente , Humanos , Imunogenicidade da Vacina , Reação no Local da Injeção , Injeções Intramusculares , Masculino , África do Sul , Adulto Jovem
9.
PLoS Med ; 17(5): e1003117, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32442195

RESUMO

BACKGROUND: DNA plasmids promise a pragmatic alternative to viral vectors for prime-boost HIV-1 vaccines. We evaluated DNA plasmid versus canarypox virus (ALVAC) primes in 2 randomized, double-blind, placebo-controlled trials in southern Africa with harmonized trial designs. HIV Vaccine Trials Network (HVTN) 111 tested DNA plasmid prime by needle or needleless injection device (Biojector) and DNA plasmid plus gp120 protein plus MF59 adjuvant boost. HVTN 100 tested ALVAC prime and ALVAC plus gp120 protein plus MF59 adjuvant boost (same protein/adjuvant as HVTN 111) by needle. METHODS AND FINDINGS: The primary endpoints for this analysis were binding antibody (bAb) responses to HIV antigens (gp120 from strains ZM96, 1086, and TV1; variable 1 and 2 [V1V2] regions of gp120 from strains TV1, 1086, and B.CaseA, as 1086 V1V2 and B.CaseA were correlates of risk in the RV144 efficacy trial), neutralizing antibody (nAb) responses to pseudoviruses TV1c8.2 and MW925.26, and cellular responses to vaccine-matched antigens (envelope [Env] from strains ZM96, 1086, and TV1; and Gag from strains LAI and ZM96) at month 6.5, two weeks after the fourth vaccination. Per-protocol cohorts included vaccine recipients from HVTN 100 (n = 186, 60% male, median age 23 years) enrolled between February 9, 2015, and May 26, 2015 and from HVTN 111 (n = 56, 48% male, median age 24 years) enrolled between June 21, 2016, and July 13, 2017. IgG bAb response rates were 100% to 3 Env gp120 antigens in both trials. Response rates to V1V2 were lower and similar in both trials except to vaccine-matched 1086 V1V2, with rates significantly higher for the DNA-primed regimen than the ALVAC-primed regimen: 96.6% versus 72.7% (difference = 23.9%, 95% CI 15.6%-32.2%, p < 0.001). Among positive responders, bAb net mean fluorescence intensity (MFI) was significantly higher with the DNA-primed regimen than ALVAC-primed for 1086 V1V2 (geometric mean [GM] 2,833.3 versus 1,200.9; ratio = 2.36, 95% CI 1.42-3.92, p < 0.001) and B.CaseA V1V2 (GM 2314.0 versus 744.6, ratio = 3.11, 95% CI 1.51-6.38, p = 0.002). nAb response rates were >98% in both trials, with significantly higher 50% inhibitory dilution (ID50) among DNA-primed positive responders (n = 53) versus ALVAC-primed (n = 182) to tier 1A MW965.26 (GM 577.7 versus 265.7, ratio = 2.17, 95% CI 1.67-2.83, p < 0.001) and to TV1c8.2 (GM 187.3 versus 100.4, ratio = 1.87, 95% CI 1.48-2.35, p < 0.001). CD4+ T-cell response rates were significantly higher with DNA plasmid prime via Biojector than ALVAC prime (91.4% versus 52.8%, difference = 38.6%, 95% CI 20.5%-56.6%, p < 0.001 for ZM96.C; 88.0% versus 43.1%, difference = 44.9%, 95% CI 26.7%-63.1%, p < 0.001 for 1086.C; 55.5% versus 2.2%, difference = 53.3%, 95% CI 23.9%-82.7%, p < 0.001 for Gag LAI/ZM96). The study's main limitations include the nonrandomized comparison of vaccines from 2 different trials, the lack of data on immune responses to other non-vaccine-matched antigens, and the uncertain clinical significance of the observed immunological effects. CONCLUSIONS: In this study, we found that further investigation of DNA/protein regimens is warranted given enhanced immunogenicity to the V1V2 correlates of decreased HIV-1 acquisition risk identified in RV144, the only HIV vaccine trial to date to show any efficacy.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Adulto , Formação de Anticorpos/imunologia , DNA/genética , Método Duplo-Cego , Feminino , Vetores Genéticos , Antígenos HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/genética , HIV-1/imunologia , Humanos , Masculino , Plasmídeos/genética , Vacinação/métodos , Adulto Jovem
10.
Arch Virol ; 165(11): 2439-2452, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32797338

RESUMO

New HIV infections continue relentlessly in southern Africa, demonstrating the need for a vaccine to prevent HIV subtype C. In South Africa, the country with the highest number of new infections annually, HIV vaccine research has been ongoing since 2003 with collaborative public-private-philanthropic partnerships. So far, 21 clinical trials have been conducted in South Africa, investigating seven viral vectors, three DNA plasmids, four envelope proteins, five adjuvants and three monoclonal antibodies. Active vaccine candidates have spanned subtypes A, B, C, E and multi-subtype mosaic sequences. All were well tolerated. Four concepts were investigated for efficacy: rAd5-gag/pol/nef showed increased HIV acquisition in males, subtype C ALVAC/gp120/MF59 showed no preventative efficacy, and the trials for the VRC01 monoclonal antibody and Ad26.Mos4.HIV/subtype C gp140/ aluminum phosphate are ongoing. Future trials are planned with DNA/viral vector plus protein combinations in concert with pre-exposure prophylaxis, and sequential immunization studies with transmitted/founder HIV envelope to induce broadly neutralizing antibodies. Finally, passive immunization trials are underway to build on the experience with VRC01, including single and combination antibody trials with an antibody derived from a subtype-C-infected South African donor. Future consideration should be given to the evaluation of novel strategies, for example, inactivated-whole-virus vaccines.


Assuntos
Vacinas contra a AIDS/imunologia , Infecções por HIV/prevenção & controle , Vacinas contra a AIDS/administração & dosagem , Anticorpos Monoclonais/uso terapêutico , Humanos , Imunização Passiva , Ensaios Clínicos Controlados Aleatórios como Assunto , África do Sul , Resultado do Tratamento , Vacinação
11.
BMC Public Health ; 20(1): 1669, 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33160341

RESUMO

BACKGROUND: Despite multiple available HIV prevention methods, the HIV epidemic continues to affect South Africa the most. We sought to understand willingness to use actual and hypothetical HIV prevention methods among participants enrolled in a preventative HIV vaccine efficacy trial in Soweto, South Africa. METHODS: We conducted a qualitative study with 38 self-reporting HIV-uninfected and consenting 18-35 year olds participating in the HVTN 702 vaccine efficacy trial in Soweto. Using a semi-structured interview guide, five focus group discussions (FGDs) were held, stratified by age, gender and sexual orientation. The FGDs were composed of: (i) 10 heterosexual women aged 18-24 years; (ii) 9 heterosexual and bisexual women aged 25-35 years; (iii & iv) heterosexual men aged 25-35 years with 7 in both groups; and (v) 5 men aged 18-35 years who have sex with men. FGDs were audio-recorded, transcribed verbatim, translated into English and analysed using thematic analysis. RESULTS: We present five main themes: (i) long-lasting methods are preferable; (ii) condoms are well-known but not preferred for use; (iii) administration route of HIV prevention method is a consideration for the user; (iv) ideal HIV prevention methods should blend into the lifestyle of the user; and the perception that (v) visible prevention methods indicate sexual indiscretion. CONCLUSIONS: The participants' candour about barriers to condom and daily oral pre-exposure prophylaxis (PrEP) use, and expressed preferences for long-lasting, discreet, lifestyle-friendly methods reveal a gap in the biomedical prevention market aiming to reduce sexually acquired HIV in South Africa. Product developers should consider long-acting injectable formulations, such as vaccines, passive antibodies and chemoprophylaxis, for HIV prevention technologies. Future innovations in HIV prevention products may need to address the desire for the method to blend easily into lifestyles, such as food-medication formulations.


Assuntos
Infecções por HIV , Profilaxia Pré-Exposição , Adolescente , Adulto , Preservativos , Feminino , Infecções por HIV/prevenção & controle , Humanos , Masculino , Comportamento Sexual , África do Sul , Adulto Jovem
12.
BMC Health Serv Res ; 20(1): 404, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32393224

RESUMO

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.


Assuntos
Instituições de Assistência Ambulatorial/normas , Infecções por HIV/diagnóstico , Satisfação do Paciente/estatística & dados numéricos , Adolescente , Adulto , Aconselhamento , Estudos Transversais , Feminino , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Doenças não Transmissíveis , Aceitação pelo Paciente de Cuidados de Saúde , Estudos Prospectivos , Setor Público , África do Sul , Adulto Jovem
15.
PLoS Biol ; 14(3): e1002372, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26933962

RESUMO

In the last 15 years, antiretroviral therapy (ART) has been the most globally impactful life-saving development of medical research. Antiretrovirals (ARVs) are used with great success for both the treatment and prevention of HIV infection. Despite these remarkable advances, this epidemic grows relentlessly worldwide. Over 2.1 million new infections occur each year, two-thirds in women and 240,000 in children. The widespread elimination of HIV will require the development of new, more potent prevention tools. Such efforts are imperative on a global scale. However, it must also be recognised that true containment of the epidemic requires the development and widespread implementation of a scientific advancement that has eluded us to date--a highly effective vaccine. Striving for such medical advances is what is required to achieve the end of AIDS.


Assuntos
Infecções por HIV/prevenção & controle , Vacinas contra a AIDS , Anti-Infecciosos Locais , Antirretrovirais/uso terapêutico , Anticorpos Neutralizantes , Humanos , Pediatria
17.
PLoS Pathog ; 12(7): e1005742, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27434311

RESUMO

The development of biomedical interventions to reduce acquisition of HIV-1 infection remains a global priority, however their potential effectiveness is challenged by very high HIV-1 envelope diversity. Two large prophylactic trials in high incidence, clade C epidemic regions in southern Africa are imminent; passive administration of the monoclonal antibody VRC01, and active immunization with a clade C modified RV144-like vaccines. We have created a large representative panel of C clade viruses to enable assessment of antibody responses to vaccines and natural infection in Southern Africa, and we investigated the genotypic and neutralization properties of recently transmitted clade C viruses to determine how viral diversity impacted antibody recognition. We further explore the implications of these findings for the potential effectiveness of these trials. A panel of 200 HIV-1 Envelope pseudoviruses was constructed from clade C viruses collected within the first 100 days following infection. Viruses collected pre-seroconversion were significantly more resistant to serum neutralization compared to post-seroconversion viruses (p = 0.001). Over 13 years of the study as the epidemic matured, HIV-1 diversified (p = 0.0009) and became more neutralization resistant to monoclonal antibodies VRC01, PG9 and 4E10. When tested at therapeutic levels (10ug/ml), VRC01 only neutralized 80% of viruses in the panel, although it did exhibit potent neutralization activity against sensitive viruses (IC50 titres of 0.42 µg/ml). The Gp120 amino acid similarity between the clade C panel and candidate C-clade vaccine protein boosts (Ce1086 and TV1) was 77%, which is 8% more distant than between CRF01_AE viruses and the RV144 CRF01_AE immunogen. Furthermore, two vaccine signature sites, K169 in V2 and I307 in V3, associated with reduced infection risk in RV144, occurred less frequently in clade C panel viruses than in CRF01_AE viruses from Thailand. Increased resistance of pre-seroconversion viruses and evidence of antigenic drift highlights the value of using panels of very recently transmitted viruses and suggests that interventions may need to be modified over time to track the changing epidemic. Furthermore, high divergence such as that observed in the older clade C epidemic in southern Africa may impact vaccine efficacy, although the correlates of infection risk are yet to be defined in the clade C setting. Findings from this study of acute/early clade C viruses will aid vaccine development, and enable identification of new broad and potent antibodies to combat the HIV-1 C-clade epidemic in southern Africa.


Assuntos
Vacinas contra a AIDS/imunologia , Infecções por HIV/imunologia , HIV-1/genética , HIV-1/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/imunologia , Anticorpos Amplamente Neutralizantes , Ensaios Clínicos como Assunto , Anticorpos Anti-HIV , Proteína gp120 do Envelope de HIV/imunologia , Humanos , Imunização Passiva/métodos , Filogenia , Vacinação/métodos
18.
AIDS Behav ; 22(7): 2312-2321, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29594618

RESUMO

Recall and social desirability bias undermine self-report of paper-and-pencil questionnaires. Mobile phone questionnaires may overcome these challenges. We assessed and compared sexual risk behavior reporting via in-clinic paper-and-pencil and mobile phone questionnaires. HVTN 915 was a prospective cohort study of 50 adult women in Soweto, who completed daily mobile phone, and eight interviewer-administered in-clinic questionnaires over 12 weeks to assess sexual risk. Daily mobile phone response rates were 82% (n = 3486/4500); 45% (n = 1565/3486) reported vaginal sex (median sex acts 2 (IQR: 1-3)) within 24 h and 40% (n = 618/1565) consistent condom. Vaginal sex reporting was significantly higher via mobile phone across all visits (p < 0.0001). There was no significant difference in condom use reporting by mobile phone and in-clinic paper-based questionnaires across all visits (p = 0.5134). The results show high adherence and reporting of sex on the mobile phone questionnaire. We demonstrate feasibility in collecting mobile phone sexual risk data.


Assuntos
Telefone Celular , Preservativos/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Adulto , Instituições de Assistência Ambulatorial , Estudos de Coortes , Coleta de Dados , Estudos de Viabilidade , Feminino , Infecções por HIV , Humanos , Estudos Prospectivos , Medição de Risco , Assunção de Riscos , Sexo Seguro/estatística & dados numéricos , Autorrelato , África do Sul , Inquéritos e Questionários , Adulto Jovem
19.
PLoS Med ; 14(2): e1002241, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28245236

RESUMO

In a Perspective, Linda-Gail Bekker and Glenda Gray discuss HIV vaccine development.


Assuntos
Vacinas contra a AIDS/imunologia , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Vacinas contra a AIDS/isolamento & purificação , África Austral , Humanos
20.
J Infect Dis ; 214(3): 379-89, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-26951820

RESUMO

BACKGROUND: HLA strongly influences human immunodeficiency virus type 1 (HIV-1) disease progression. A major contributory mechanism is via the particular HLA-presented HIV-1 epitopes that are recognized by CD8(+) T-cells. Different populations vary considerably in the HLA alleles expressed. We investigated the HLA-specific impact of the MRKAd5 HIV-1 Gag/Pol/Nef vaccine in a subset of the infected Phambili cohort in whom the disease-susceptible HLA-B*58:02 is highly prevalent. METHODS: Viral loads, CD4(+) T-cell counts, and enzyme-linked immunospot assay-determined anti-HIV-1 CD8(+) T-cell responses for a subset of infected antiretroviral-naive Phambili participants, selected according to sample availability, were analyzed. RESULTS: Among those expressing disease-susceptible HLA-B*58:02, vaccinees had a lower chronic viral set point than placebo recipients (median, 7240 vs 122 500 copies/mL; P = .01), a 0.76 log10 lower longitudinal viremia level (P = .01), and slower progression to a CD4(+) T-cell count of <350 cells/mm(3) (P = .02). These differences were accompanied by a higher Gag-specific breadth (4.5 vs 1 responses; P = .04) and magnitude (2300 vs 70 spot-forming cells/10(6) peripheral blood mononuclear cells; P = .06) in vaccinees versus placebo recipients. CONCLUSIONS: In addition to the known enhancement of HIV-1 acquisition resulting from the MRKAd5 HIV-1 vaccine, these findings in a nonrandomized subset of enrollees show an HLA-specific vaccine effect on the time to CD4(+) T-cell count decline and viremia level after infection and the potential for vaccines to differentially alter disease outcome according to population HLA composition. CLINICAL TRIALS REGISTRATION: NCT00413725, DOH-27-0207-1539.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , Antígenos HLA-B/genética , Vacinas contra a SAIDS/imunologia , Carga Viral , Adulto , Alelos , Contagem de Linfócito CD4 , ELISPOT , Feminino , Humanos , Masculino , Placebos/administração & dosagem , Vacinas contra a SAIDS/administração & dosagem , Adulto Jovem
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