Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
1.
Lancet HIV ; 7(6): e422-e433, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32504575

RESUMO

BACKGROUND: In settings with high HIV prevalence and treatment coverage, such as Botswana, it is unknown whether uptake of HIV prevention and treatment interventions can be increased further. We sought to determine whether a community-based intervention to identify and rapidly treat people living with HIV, and support male circumcision could increase population levels of HIV diagnosis, treatment, viral suppression, and male circumcision in Botswana. METHODS: The Ya Tsie Botswana Combination Prevention Project study was a pair-matched cluster-randomised trial done in 30 communities across Botswana done from Oct 30, 2013, to June 30, 2018. 15 communities were randomly assigned to receive HIV prevention and treatment interventions, including enhanced HIV testing, earlier antiretroviral therapy (ART), and strengthened male circumcision services, and 15 received standard of care. The first primary endpoint of HIV incidence has already been reported. In this Article, we report findings for the second primary endpoint of population uptake of HIV prevention services, as measured by proportion of people known to be HIV-positive or tested HIV-negative in the preceding 12 months; proportion of people living with HIV diagnosed and on ART; proportion of people living with HIV on ART with viral suppression; and proportion of HIV-negative men circumcised. A longitudinal cohort of residents aged 16-64 years from a random, approximately 20% sample of households across the 15 communities was enrolled to assess baseline uptake of study outcomes; we also administered an end-of-study survey to all residents not previously enrolled in the longitudinal cohort to provide study end coverage estimates. Differences in intervention uptake over time by randomisation group were tested via paired Student's t test. The study has been completed and is registered with ClinicalTrials.gov (NCT01965470). FINDINGS: In the six communities participating in the end-of-study survey, 2625 residents (n=1304 from standard-of-care communities, n=1321 from intervention communities) were enrolled into the 20% longitudinal cohort at baseline from Oct 30, 2013, to Nov 24, 2015. In the same communities, 10 791 (86%) of 12 489 eligible enumerated residents not previously enrolled in the longitudinal cohort participated in the end-of-study survey from March 30, 2017, to Feb 25, 2018 (5896 in intervention and 4895 in standard-of-care communities). At study end, in intervention communities, 1228 people living with HIV (91% of 1353) were on ART; 1166 people living with HIV (88% of 1321 with available viral load) were virally suppressed, and 673 HIV-negative men (40% of 1673) were circumcised in intervention communities. After accounting for baseline differences, at study end the proportion of people living with HIV who were diagnosed was significantly higher in intervention communities (absolute increase of 9% to 93%) compared with standard-of-care communities (absolute increase of 2% to 88%; prevalence ratio [PR] 1·08 [95% CI 1·02-1·14], p=0·032). Population levels of ART, viral suppression, and male circumcision increased from baseline in both groups, with greater increases in intervention communities (ART PR 1·12 [95% CI 1·07-1·17], p=0·018; viral suppression 1·13 [1·09-1·17], p=0·017; male circumcision 1·26 [1·17-1·35], p=0·029). INTERPRETATION: It is possible to achieve very high population levels of HIV testing and treatment in a high-prevalence setting. Maintaining these coverage levels over the next decade could substantially reduce HIV transmission and potentially eliminate the epidemic in these areas. FUNDING: US President's Emergency Plan for AIDS Relief through the Centers for Disease Control and Prevention.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Circuncisão Masculina/estatística & dados numéricos , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , HIV-1/fisiologia , Adolescente , Adulto , Terapia Antirretroviral de Alta Atividade , Botsuana/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Humanos , Estudos Longitudinais , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Prevalência , Inquéritos e Questionários , Carga Viral , Adulto Jovem
3.
PLoS One ; 10(8): e0135602, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26267867

RESUMO

BACKGROUND: The expansion of combination antiretroviral treatment (ART) in southern Africa has dramatically reduced mortality due to AIDS-related infections, but the impact of ART on cancer incidence in the region is unknown. We sought to describe trends in cancer incidence in Botswana during implementation of the first public ART program in Africa. METHODS: We included 8479 incident cases from the Botswana National Cancer Registry during a period of significant ART expansion in Botswana, 2003-2008, when ART coverage increased from 7.3% to 82.3%. We fit Poisson models of age-adjusted cancer incidence and counts in the total population, and in an inverse probability weighted population with known HIV status, over time and estimated ART coverage. FINDINGS: During this period 61.6% of cancers were diagnosed in HIV-infected individuals and 45.4% of all cancers in men and 36.4% of all cancers in women were attributable to HIV. Age-adjusted cancer incidence decreased in the HIV infected population by 8.3% per year (95% CI -14.1 to -2.1%). However, with a progressively larger and older HIV population the annual number of cancers diagnosed remained constant (0.0% annually, 95% CI -4.3 to +4.6%). In the overall population, incidence of Kaposi's sarcoma decreased (4.6% annually, 95% CI -6.9 to -2.2), but incidence of non-Hodgkin lymphoma (+11.5% annually, 95% CI +6.3 to +17.0%) and HPV-associated cancers increased (+3.9% annually, 95% CI +1.4 to +6.5%). Age-adjusted cancer incidence among individuals without HIV increased 7.5% per year (95% CI +1.4 to +15.2%). INTERPRETATION: Expansion of ART in Botswana was associated with decreased age-specific cancer risk. However, an expanding and aging population contributed to continued high numbers of incident cancers in the HIV population. Increased capacity for early detection and treatment of HIV-associated cancer needs to be a new priority for programs in Africa.


Assuntos
Infecções por HIV/epidemiologia , Neoplasias/epidemiologia , Antineoplásicos/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Botsuana/epidemiologia , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Incidência , Masculino , Pessoa de Meia-Idade
4.
Proc Natl Acad Sci U S A ; 111(50): E5393-400, 2014 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-25453107

RESUMO

It is widely believed that epidemics in new hosts diminish in virulence over time, with natural selection favoring pathogens that cause minimal disease. However, a tradeoff frequently exists between high virulence shortening host survival on the one hand but allowing faster transmission on the other. This is the case in HIV infection, where high viral loads increase transmission risk per coital act but reduce host longevity. We here investigate the impact on HIV virulence of HIV adaptation to HLA molecules that protect against disease progression, such as HLA-B*57 and HLA-B*58:01. We analyzed cohorts in Botswana and South Africa, two countries severely affected by the HIV epidemic. In Botswana, where the epidemic started earlier and adult seroprevalence has been higher, HIV adaptation to HLA including HLA-B*57/58:01 is greater compared with South Africa (P = 7 × 10(-82)), the protective effect of HLA-B*57/58:01 is absent (P = 0.0002), and population viral replicative capacity is lower (P = 0.03). These data suggest that viral evolution is occurring relatively rapidly, and that adaptation of HIV to the most protective HLA alleles may contribute to a lowering of viral replication capacity at the population level, and a consequent reduction in HIV virulence over time. The potential role in this process played by increasing antiretroviral therapy (ART) access is also explored. Models developed here suggest distinct benefits of ART, in addition to reducing HIV disease and transmission, in driving declines in HIV virulence over the course of the epidemic, thereby accelerating the effects of HLA-mediated viral adaptation.


Assuntos
Adaptação Biológica/genética , Evolução Molecular , Infecções por HIV/epidemiologia , HIV/genética , HIV/patogenicidade , Antígenos HLA-B/genética , Adulto , Sequência de Bases , Botsuana/epidemiologia , Estudos de Coortes , Infecções por HIV/transmissão , Antígenos HLA-B/imunologia , Humanos , Dados de Sequência Molecular , Análise de Sequência de DNA , Estudos Soroepidemiológicos , África do Sul/epidemiologia , Virulência
5.
J Immunol ; 174(11): 7179-85, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15905562

RESUMO

The utility of recombinant adenovirus serotype 5 (rAd5) vector-based vaccines for HIV-1 and other pathogens will likely be limited by the high prevalence of pre-existing Ad5-specific neutralizing Abs (NAbs) in human populations. However, the immunodominant targets of Ad5-specific NAbs in humans remain poorly characterized. In this study, we assess the titers and primary determinants of Ad5-specific NAbs in individuals from both the United States and the developing world. Importantly, median Ad5-specific NAb titers were >10-fold higher in sub-Saharan Africa compared with the United States. Moreover, hexon-specific NAb titers were 4- to 10-fold higher than fiber-specific NAb titers in these cohorts by virus neutralization assays using capsid chimeric viruses. We next performed adoptive transfer studies in mice to evaluate the functional capacity of hexon- and fiber-specific NAbs to suppress the immunogenicity of a prototype rAd5-Env vaccine. Hexon-specific NAbs were remarkably efficient at suppressing Env-specific immune responses elicited by the rAd5 vaccine. In contrast, fiber-specific NAbs exerted only minimal suppressive effects on rAd5 vaccine immunogenicity. These data demonstrate that functionally significant Ad5-specific NAbs are directed primarily against the Ad5 hexon protein in both humans and mice. These studies suggest a potential strategy for engineering novel Ad5 vectors to evade dominant Ad5-specific NAbs.


Assuntos
Adenovírus Humanos/imunologia , Anticorpos Antivirais/fisiologia , Proteínas do Capsídeo/imunologia , Vetores Genéticos/imunologia , Vacinas de DNA/imunologia , Vacinas Virais/imunologia , Adenovírus Humanos/genética , Adulto , Animais , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/sangue , Proteínas do Capsídeo/administração & dosagem , Proteínas do Capsídeo/genética , Relação Dose-Resposta Imunológica , Vetores Genéticos/administração & dosagem , Vetores Genéticos/metabolismo , Humanos , Epitopos Imunodominantes/genética , Epitopos Imunodominantes/imunologia , Epitopos Imunodominantes/metabolismo , Imunossupressores/metabolismo , Imunossupressores/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Testes de Neutralização , Estudos Soroepidemiológicos , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA