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1.
N Engl J Med ; 381(9): 827-840, 2019 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-31329379

RESUMO

BACKGROUND: A preliminary safety signal for neural-tube defects was previously reported in association with dolutegravir exposure from the time of conception, which has affected choices of antiretroviral treatment (ART) for human immunodeficiency virus (HIV)-infected women of reproductive potential. The signal can now be evaluated with data from follow-up of additional pregnancies. METHODS: We conducted birth-outcomes surveillance at hospitals throughout Botswana, expanding from 8 to 18 sites in 2018. Trained midwives performed surface examinations of all live-born and stillborn infants. Research assistants photographed abnormalities after maternal consent was obtained. The prevalence of neural-tube defects and major external structural defects according to maternal HIV infection and ART exposure status was determined. In the primary analyses, we used the Newcombe method to evaluate differences in prevalence with 95% confidence intervals. RESULTS: From August 2014 through March 2019, surveillance captured 119,477 deliveries; 119,033 (99.6%) had an infant surface examination that could be evaluated, and 98 neural-tube defects were identified (0.08% of deliveries). Among 1683 deliveries in which the mother was taking dolutegravir at conception, 5 neural-tube defects were found (0.30% of deliveries); the defects included two instances of myelomeningocele, one of anencephaly, one of encephalocele, and one of iniencephaly. In comparison, 15 neural-tube defects were found among 14,792 deliveries (0.10%) in which the mother was taking any non-dolutegravir ART at conception, 3 among 7959 (0.04%) in which the mother was taking efavirenz at conception, 1 among 3840 (0.03%) in which the mother started dolutegravir treatment during pregnancy, and 70 among 89,372 (0.08%) in HIV-uninfected mothers. The prevalence of neural-tube defects was higher in association with dolutegravir treatment at conception than with non-dolutegravir ART at conception (difference, 0.20 percentage points; 95% confidence interval [CI], 0.01 to 0.59) or with other types of ART exposure. Major external structural defects were found in 0.95% of deliveries among women exposed to dolutegravir at conception and 0.68% of those among women exposed to non-dolutegravir ART at conception (difference, 0.27 percentage points; 95% CI, -0.13 to 0.87). CONCLUSIONS: The prevalence of neural-tube defects was slightly higher in association with dolutegravir exposure at conception than with other types of ART exposure at conception (3 per 1000 deliveries vs. 1 per 1000 deliveries). (Funded by the National Institutes of Health.).


Assuntos
Antirretrovirais/efeitos adversos , Anormalidades Congênitas/epidemiologia , Infecções por HIV/tratamento farmacológico , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , Defeitos do Tubo Neural/induzido quimicamente , Complicações Infecciosas na Gravidez/tratamento farmacológico , Adulto , Antirretrovirais/uso terapêutico , Botsuana/epidemiologia , Quimioterapia Combinada , Feminino , Feto/efeitos dos fármacos , Inibidores de Integrase de HIV/efeitos adversos , Inibidores de Integrase de HIV/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Humanos , Recém-Nascido , Defeitos do Tubo Neural/epidemiologia , Oxazinas , Piperazinas , Vigilância da População , Gravidez , Prevalência , Piridonas , Fatores Socioeconômicos
2.
N Engl J Med ; 381(3): 230-242, 2019 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-31314967

RESUMO

BACKGROUND: The feasibility of reducing the population-level incidence of human immunodeficiency virus (HIV) infection by increasing community coverage of antiretroviral therapy (ART) and male circumcision is unknown. METHODS: We conducted a pair-matched, community-randomized trial in 30 rural or periurban communities in Botswana from 2013 to 2018. Participants in 15 villages in the intervention group received HIV testing and counseling, linkage to care, ART (started at a higher CD4 count than in standard care), and increased access to male circumcision services. The standard-care group also consisted of 15 villages. Universal ART became available in both groups in mid-2016. We enrolled a random sample of participants from approximately 20% of households in each community and measured the incidence of HIV infection through testing performed approximately once per year. The prespecified primary analysis was a permutation test of HIV incidence ratios. Pair-stratified Cox models were used to calculate 95% confidence intervals. RESULTS: Of 12,610 enrollees (81% of eligible household members), 29% were HIV-positive. Of the 8974 HIV-negative persons (4487 per group), 95% were retested for HIV infection over a median of 29 months. A total of 57 participants in the intervention group and 90 participants in the standard-care group acquired HIV infection (annualized HIV incidence, 0.59% and 0.92%, respectively). The unadjusted HIV incidence ratio in the intervention group as compared with the standard-care group was 0.69 (P = 0.09) by permutation test (95% confidence interval [CI], 0.46 to 0.90 by pair-stratified Cox model). An end-of-trial survey in six communities (three per group) showed a significantly greater increase in the percentage of HIV-positive participants with an HIV-1 RNA level of 400 copies per milliliter or less in the intervention group (18 percentage points, from 70% to 88%) than in the standard-care group (8 percentage points, from 75% to 83%) (relative risk, 1.12; 95% CI, 1.09 to 1.16). The percentage of men who underwent circumcision increased by 10 percentage points in the intervention group and 2 percentage points in the standard-care group (relative risk, 1.26; 95% CI, 1.17 to 1.35). CONCLUSIONS: Expanded HIV testing, linkage to care, and ART coverage were associated with increased population viral suppression. (Funded by the President's Emergency Plan for AIDS Relief and others; Ya Tsie ClinicalTrials.gov number, NCT01965470.).


Assuntos
Antirretrovirais/uso terapêutico , Circuncisão Masculina , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Programas de Rastreamento , Adolescente , Adulto , Botsuana/epidemiologia , Circuncisão Masculina/estatística & dados numéricos , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Incidência , Masculino , Administração Massiva de Medicamentos , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , População Rural , Fatores Socioeconômicos , Carga Viral , Adulto Jovem
3.
J Infect Dis ; 222(10): 1670-1680, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32492145

RESUMO

BACKGROUND: Phylogenetic mapping of HIV-1 lineages circulating across defined geographical locations is promising for better understanding HIV transmission networks to design optimal prevention interventions. METHODS: We obtained near full-length HIV-1 genome sequences from people living with HIV (PLWH), including participants on antiretroviral treatment in the Botswana Combination Prevention Project, conducted in 30 Botswana communities in 2013-2018. Phylogenetic relationships among viral sequences were estimated by maximum likelihood. RESULTS: We obtained 6078 near full-length HIV-1C genome sequences from 6075 PLWH. We identified 984 phylogenetically distinct HIV-1 lineages (molecular HIV clusters) circulating in Botswana by mid-2018, with 2-27 members per cluster. Of these, dyads accounted for 62%, approximately 32% (n = 316) were found in single communities, and 68% (n = 668) were spread across multiple communities. Men in clusters were approximately 3 years older than women (median age 42 years, vs 39 years; P < .0001). In 65% of clusters, men were older than women, while in 35% of clusters women were older than men. The majority of identified viral lineages were spread across multiple communities. CONCLUSIONS: A large number of circulating phylogenetically distinct HIV-1C lineages (molecular HIV clusters) suggests highly diversified HIV transmission networks across Botswana communities by 2018.


Assuntos
Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/genética , Adolescente , Adulto , Antirreumáticos/uso terapêutico , Botsuana , Testes Diagnósticos de Rotina , Feminino , Genoma Viral , Genótipo , Infecções por HIV/tratamento farmacológico , HIV-1/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Projetos de Pesquisa , Alinhamento de Sequência , Adulto Jovem
4.
Curr HIV/AIDS Rep ; 17(5): 478-486, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32797382

RESUMO

PURPOSE OF REVIEW: Antiretroviral treatment (ART) can dramatically reduce the risk of HIV transmission, but the feasibility of scaling up HIV testing, linkage and treatment to very high population levels, and its impact on population HIV incidence, were unknown. We review key findings from a community-randomized trial in which we evaluated the impact of "universal test and treat" (UTT) on population HIV incidence in Botswana, a resource-constrained country with both high HIV prevalence and high ART coverage before study inception. RECENT FINDINGS: We conducted a community-randomized trial (the "Ya Tsie" trial or Botswana Combination Prevention Project (BCPP)) in 30 villages in Botswana from 2013 to 2018, with the goal of determining whether a combination of prevention interventions-with a focus on universal HIV testing and treatment-would reduce population-level HIV incidence. The intervention included universal HIV testing (home-based and mobile), active linkage to HIV care and treatment with patient tracing for persons not linking, universal ART coverage, rapid ART start (at the first clinic visit), and enhanced male circumcision services. Botswana had very high HIV diagnosis, treatment, and viral suppression levels (approaching the UNAIDS "90-90-90" targets) prior to intervention roll-out. By study end, we were able to exceed the overall 95-95-95 coverage target of 86%: an estimated 88% of all persons living with HIV were on ART and had viral suppression in the Ya Tsie intervention arm. In addition, annual HIV incidence was 30% lower in the intervention arm as compared with the control arm over a 29-month follow-up period. With universal HIV testing and relatively simple linkage activities, it was possible to achieve one of the highest reported population levels of HIV diagnosis, linkage to care, and viral suppression globally and to reduce population HIV incidence by about one-third over a short period of time (< 3 years). We were able to significantly increase population viral suppression and to decrease HIV incidence even in a resource-constrained setting with pre-existing very high testing and treatment coverage. Universal community-based HIV testing and tracing of individuals through the HIV care cascade were key intervention components.


Assuntos
Infecções por HIV/diagnóstico , Infecções por HIV/prevenção & controle , Teste de HIV/métodos , Programas de Rastreamento/métodos , Saúde Pública/métodos , Adulto , Antirretrovirais/uso terapêutico , Botsuana , Circuncisão Masculina , Busca de Comunicante/métodos , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Incidência , Masculino , Prevalência
5.
J Antimicrob Chemother ; 71(5): 1361-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26929269

RESUMO

OBJECTIVES: The aim of the study was to evaluate for the presence of drug resistance to HIV medications in treatment-naive individuals in Botswana. METHODS: Two different populations were evaluated for evidence of HIV drug resistance at three different geographical locations in Botswana. In the first study population, consisting of pregnant females diagnosed with HIV during pregnancy, participants were enrolled at the time of their HIV diagnosis. The second population included pre-ART enrollees at Infectious Diseases Care Clinics (IDCCs) who had a CD4 T cell count >350 cells/µL. RESULTS: A total of 422 genotypes were determined: 234 for samples from antenatal clinic (ANC) participants and 188 for samples from IDCC participants. Between 2012 and 2014, 6 of 172 (3.5%) genotypes from ANC participants exhibited transmitted drug resistance (TDR), with 3 (1.7%) showing resistance to first-line ART. In a subset of samples from Gaborone, Botswana's capital and largest city, the TDR rate was 3 in 105 (2.9%), but only 1 in 105 (1.0%) showed first-line ART resistance. Between December 2014 and April 2015, the rate of resistance to any ART in Gaborone was 6 in 62 (9.7%), with 5 (8.1%) exhibiting first-line ART resistance. CONCLUSIONS: These data demonstrate that TDR rates for HIV differ geographically and temporally in Botswana, with significant increases in TDR observed at ANCs in Gaborone between 2012 and 2015. These findings stress the importance of continued testing for TDR, particularly as access to HIV treatment increases and guidelines recommend treatment at the time of HIV diagnosis.


Assuntos
Farmacorresistência Viral , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV/efeitos dos fármacos , Adolescente , Adulto , Idoso , Botsuana/epidemiologia , Monitoramento Epidemiológico , Feminino , HIV/isolamento & purificação , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Prevalência , Adulto Jovem
6.
Br J Nutr ; 115(12): 2114-21, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27087233

RESUMO

An obesity paradox has been proposed in many conditions including HIV. Studies conducted to investigate obesity and its effect on HIV disease progression have been inconclusive and are lacking for African settings. This study investigated the relationship between overweight/obesity (BMI≥25 kg/m2) and HIV disease progression in HIV+ asymptomatic adults not on antiretroviral treatment (ART) in Botswana over 18 months. A cohort study in asymptomatic, ART-naïve, HIV+ adults included 217 participants, 139 with BMI of 18·0-24·9 kg/m2 and seventy-eight participants with BMI≥25 kg/m2. The primary outcome was time to event (≥25 % decrease in cluster of differentiation 4 (CD4) cell count) during 18 months of follow-up; secondary outcomes were time to event of CD4 cell count<250 cells/µl and AIDS-defining conditions. Proportional survival hazard models were used to compare hazard ratios (HR) on time to events of HIV disease progression over 18 months. Higher baseline BMI was associated with significantly lower risk of an AIDS-defining condition during the follow-up (HR 0·218; 95 % CI 0·068, 0·701; P=0·011). Higher fat mass at baseline was also significantly associated with decreased risk of AIDS-defining conditions during the follow-up (HR 0·855; 95 % CI 0·741, 0·987; P=0·033) and the combined outcome of having CD4 cell count≤250/µl and AIDS-defining conditions, whichever occurred earlier (HR 0·918; 95 % CI 0·847, 0·994; P=0·036). All models were adjusted for covariates. Higher BMI and fat mass among the HIV-infected, ART-naïve participants were associated with slower disease progression. Mechanistic research is needed to evaluate the association between BMI, fat mass and HIV disease progression.


Assuntos
Tecido Adiposo/metabolismo , Composição Corporal , Índice de Massa Corporal , Progressão da Doença , Infecções por HIV/complicações , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Adulto , Fármacos Anti-HIV , Botsuana , Contagem de Linfócito CD4 , Estudos de Coortes , Feminino , Humanos , Masculino , Obesidade/complicações , Modelos de Riscos Proporcionais , Carga Viral
7.
J Clin Microbiol ; 53(8): 2581-92, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26041893

RESUMO

The goal of the study was to improve the methodology of HIV genotyping for analysis of HIV drug resistance and HIV clustering. Using the protocol of Gall et al. (A. Gall, B. Ferns, C. Morris, S. Watson, M. Cotten, M. Robinson, N. Berry, D. Pillay, and P. Kellam, J Clin Microbiol 50:3838-3844, 2012, doi:10.1128/JCM.01516-12), we developed a robust methodology for amplification of two large fragments of viral genome covering about 80% of the unique HIV-1 genome sequence. Importantly, this method can be applied to both viral RNA and proviral DNA amplification templates, allowing genotyping in HIV-infected subjects with suppressed viral loads (e.g., subjects on antiretroviral therapy [ART]). The two amplicons cover critical regions across the HIV-1 genome (including pol and env), allowing analysis of mutations associated with resistance to protease inhibitors, reverse transcriptase inhibitors (nucleoside reverse transcriptase inhibitors [NRTIs] and nonnucleoside reverse transcriptase inhibitors [NNRTIs]), integrase strand transfer inhibitors, and virus entry inhibitors. The two amplicons generated span 7,124 bp, providing substantial sequence length and numbers of informative sites for comprehensive phylogenic analysis and greater refinement of viral linkage analyses in HIV prevention studies. The long-range HIV genotyping from proviral DNA was successful in about 90% of 212 targeted blood specimens collected in a cohort where the majority of patients had suppressed viral loads, including 65% of patients with undetectable levels of HIV-1 RNA loads. The generated amplicons could be sequenced by different methods, such as population Sanger sequencing, single-genome sequencing, or next-generation ultradeep sequencing. The developed method is cost-effective-the cost of the long-range HIV genotyping is under $140 per subject (by Sanger sequencing)-and has the potential to enable the scale up of public health HIV prevention interventions.


Assuntos
DNA Viral/genética , Farmacorresistência Viral , Genótipo , Técnicas de Genotipagem/métodos , Infecções por HIV/virologia , HIV-1/classificação , RNA Viral/genética , Análise por Conglomerados , Análise Custo-Benefício , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Estudos Longitudinais , Mutação , Técnicas de Amplificação de Ácido Nucleico , Análise de Sequência de DNA
8.
J Virol ; 87(10): 5732-45, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23487450

RESUMO

Human immunodeficiency virus type 1 (HIV-1) Tat is a mediator of viral transcription and is involved in the control of virus replication. However, associations between HIV-1 Tat diversity and functional effects during primary HIV-1 infection are still unclear. We estimated selection pressures in tat exon 1 using the mixed-effects model of evolution with 672 viral sequences generated from 20 patients infected with HIV-1 subtype C (HIV-1C) over 500 days postseroconversion. tat exon 1 residues 3, 4, 21, 24, 29, 39, and 68 were under positive selection, and we established that specific amino acid signature patterns were apparent in primary HIV-1C infection compared with chronic infection. We assessed the impact of these mutations on long terminal repeat (LTR) activity and found that Tat activity was negatively affected by the Ala(21) substitution identified in 13/20 (65%) of patients, which reduced LTR activity by 88% (± 1%) (P < 0.001). The greatest increase in Tat activity was seen with the Gln(35)/Lys(39) double mutant that resulted in an additional 49% (± 14%) production of LTR-driven luciferase (P = 0.012). There was a moderate positive correlation between Tat-mediated LTR activity and HIV-1 RNA in plasma (P = 0.026; r = 0.400) after 180 days postseroconversion that was reduced by 500 days postseroconversion (P = 0.043; r = 0.266). Although Tat activation of the LTR is not a strong predictor of these clinical variables, there are significant linear relationships between Tat transactivation and patients' plasma viral loads and CD4 counts, highlighting the complex interplay between Tat mutations in early HIV-1C infection.


Assuntos
Infecções por HIV/virologia , HIV-1/fisiologia , Replicação Viral , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Adulto , Substituição de Aminoácidos , Contagem de Linfócito CD4 , Evolução Molecular , Feminino , Variação Genética , Repetição Terminal Longa de HIV/fisiologia , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Masculino , Mutação de Sentido Incorreto , Plasma/virologia , Seleção Genética , Transcrição Gênica , Carga Viral , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética
9.
Clin Trials ; 11(3): 309-318, 2014 06.
Artigo em Inglês | MEDLINE | ID: mdl-24651566

RESUMO

Background Cluster randomized trials have been utilized to evaluate the effectiveness of HIV prevention strategies on reducing incidence. Design of such studies must take into account possible correlation of outcomes within randomized units. Purpose To discuss power and sample size considerations for cluster randomized trials of combination HIV prevention, using an HIV prevention study in Botswana as an illustration. Methods We introduce a new agent-based model to simulate the community-level impact of a combination prevention strategy and investigate how correlation structure within a community affects the coefficient of variation - an essential parameter in designing a cluster randomized trial. Results We construct collections of sexual networks and then propagate HIV on them to simulate the disease epidemic. Increasing level of sexual mixing between intervention and standard-of-care (SOC) communities reduces the difference in cumulative incidence in the two sets of communities. Fifteen clusters per arm and 500 incidence cohort members per community provide 95% power to detect the projected difference in cumulative HIV incidence between SOC and intervention communities (3.93% and 2.34%) at the end of the third study year, using a coefficient of variation 0.25. Although available formulas for calculating sample size for cluster randomized trials can be derived by assuming an exchangeable correlation structure within clusters, we show that deviations from this assumption do not generally affect the validity of such formulas. Limitations We construct sexual networks based on data from Likoma Island, Malawi, and base disease progression on longitudinal estimates from an incidence cohort in Botswana and in Durban as well as a household survey in Mochudi, Botswana. Network data from Botswana and larger sample sizes to estimate rates of disease progression would be useful in assessing the robustness of our model results. Conclusion Epidemic modeling plays a critical role in planning and evaluating interventions for prevention. Simulation studies allow us to take into consideration available information on sexual network characteristics, such as mixing within and between communities as well as coverage levels for different prevention modalities in the combination prevention package.


Assuntos
Infecções por HIV/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamanho da Amostra , Botsuana , Humanos , Incidência , Projetos de Pesquisa
10.
AIDS ; 2024 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-39497537

RESUMO

OBJECTIVE: To identify predictors of HIV acquisition in Botswana. DESIGN: We applied machine learning approaches to identify HIV risk predictors using existing data from a large, well-characterized HIV incidence cohort. METHODS: We applied machine learning (randomForestSRC) to analyze data from a large population-based HIV incidence cohort enrolled in a cluster-randomized HIV prevention trial in 30 communities across Botswana. We sought to identify the most important risk factors for HIV acquisition, starting with 110 potential predictors. RESULTS: During a median 29-month follow-up of 8,551 HIV-negative adults, 147 (1.7%) acquired HIV. Our machine learning analysis found that for females, the most important variables for predicting HIV acquisition were the use of injectable hormonal contraception, frequency of sex in the prior 3 months with the most recent partner and residing in a community with HIV prevalence of 29% or higher. For the small proportion (0.3%) of females who had all three risk factors, their estimated probability of acquiring HIV during 29 months of follow-up was 34% (approximate annual incidence of 14%). For males, non-long-term relationships with the most recent partner and community HIV prevalence of 34% or higher were the most important HIV risk predictors. The 6% of males who had both risk factors had a 5.1% probability of acquiring HIV during the follow-up period (approximate annual incidence of 2.1%). CONCLUSIONS: Machine learning approaches allowed us to analyze a large number of variables to efficiently identify key factors strongly predictive of HIV risk. These factors could help target HIV prevention interventions in Botswana. CLINICAL TRIALS REGISTRATION: NCT01965470.

11.
N Engl J Med ; 362(24): 2282-94, 2010 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-20554983

RESUMO

BACKGROUND: The most effective highly active antiretroviral therapy (HAART) to prevent mother-to-child transmission of human immunodeficiency virus type 1 (HIV-1) in pregnancy and its efficacy during breast-feeding are unknown. METHODS: We randomly assigned 560 HIV-1-infected pregnant women (CD4+ count, > or = 200 cells per cubic millimeter) to receive coformulated abacavir, zidovudine, and lamivudine (the nucleoside reverse-transcriptase inhibitor [NRTI] group) or lopinavir-ritonavir plus zidovudine-lamivudine (the protease-inhibitor group) from 26 to 34 weeks' gestation through planned weaning by 6 months post partum. A total of 170 women with CD4+ counts of less than 200 cells per cubic millimeter received nevirapine plus zidovudine-lamivudine (the observational group). Infants received single-dose nevirapine and 4 weeks of zidovudine. RESULTS: The rate of virologic suppression to less than 400 copies per milliliter was high and did not differ significantly among the three groups at delivery (96% in the NRTI group, 93% in the protease-inhibitor group, and 94% in the observational group) or throughout the breast-feeding period (92% in the NRTI group, 93% in the protease-inhibitor group, and 95% in the observational group). By 6 months of age, 8 of 709 live-born infants (1.1%) were infected (95% confidence interval [CI], 0.5 to 2.2): 6 were infected in utero (4 in the NRTI group, 1 in the protease-inhibitor group, and 1 in the observational group), and 2 were infected during the breast-feeding period (in the NRTI group). Treatment-limiting adverse events occurred in 2% of women in the NRTI group, 2% of women in the protease-inhibitor group, and 11% of women in the observational group. CONCLUSIONS: All regimens of HAART from pregnancy through 6 months post partum resulted in high rates of virologic suppression, with an overall rate of mother-to-child transmission of 1.1%. (ClinicalTrials.gov number, NCT00270296.)


Assuntos
Terapia Antirretroviral de Alta Atividade , Aleitamento Materno , Infecções por HIV/transmissão , HIV-1 , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez/tratamento farmacológico , Adulto , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Contagem de Linfócito CD4 , Feminino , Seguimentos , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Lactente , Recém-Nascido , Masculino , Neutropenia/induzido quimicamente , Nevirapina/uso terapêutico , Cooperação do Paciente , Gravidez , RNA Viral/sangue , Fatores de Risco , Carga Viral/efeitos dos fármacos , Adulto Jovem , Zidovudina/uso terapêutico
12.
N Engl J Med ; 362(5): 427-39, 2010 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-20089951

RESUMO

BACKGROUND: Most persons who are infected with human immunodeficiency virus type 1 (HIV-1) are also infected with herpes simplex virus type 2 (HSV-2), which is frequently reactivated and is associated with increased plasma and genital levels of HIV-1. Therapy to suppress HSV-2 reduces the frequency of reactivation of HSV-2 as well as HIV-1 levels, suggesting that suppression of HSV-2 may reduce the risk of transmission of HIV-1. METHODS: We conducted a randomized, placebo-controlled trial of suppressive therapy for HSV-2 (acyclovir at a dose of 400 mg orally twice daily) in couples in which only one of the partners was seropositive for HIV-1 (CD4 count, > or = 250 cells per cubic millimeter) and that partner was also infected with HSV-2 and was not taking antiretroviral therapy at the time of enrollment. The primary end point was transmission of HIV-1 to the partner who was not initially infected with HIV-1; linkage of transmissions was assessed by means of genetic sequencing of viruses. RESULTS: A total of 3408 couples were enrolled at 14 sites in Africa. Of the partners who were infected with HIV-1, 68% were women, and the baseline median CD4 count was 462 cells per cubic millimeter. Of 132 HIV-1 seroconversions that occurred after randomization (an incidence of 2.7 per 100 person-years), 84 were linked within couples by viral sequencing: 41 in the acyclovir group and 43 in the placebo group (hazard ratio with acyclovir, 0.92, 95% confidence interval [CI], 0.60 to 1.41; P=0.69). Suppression with acyclovir reduced the mean plasma concentration of HIV-1 by 0.25 log(10) copies per milliliter (95% CI, 0.22 to 0.29; P<0.001) and the occurrence of HSV-2-positive genital ulcers by 73% (risk ratio, 0.27; 95% CI, 0.20 to 0.36; P<0.001). A total of 92% of the partners infected with HIV-1 and 84% of the partners not infected with HIV-1 remained in the study for 24 months. The level of adherence to the dispensed study drug was 96%. No serious adverse events related to acyclovir were observed. CONCLUSIONS: Daily acyclovir therapy did not reduce the risk of transmission of HIV-1, despite a reduction in plasma HIV-1 RNA of 0.25 log(10) copies per milliliter and a 73% reduction in the occurrence of genital ulcers due to HSV-2. (ClinicalTrials.gov number, NCT00194519.)


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Aciclovir/uso terapêutico , Antivirais/uso terapêutico , Infecções por HIV/transmissão , HIV-1 , Herpes Genital/tratamento farmacológico , Herpesvirus Humano 2 , Aciclovir/efeitos adversos , Adolescente , Adulto , Antivirais/efeitos adversos , Contagem de Linfócito CD4 , Feminino , Seguimentos , Infecções por HIV/complicações , HIV-1/genética , HIV-1/isolamento & purificação , Herpes Genital/complicações , Humanos , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Cooperação do Paciente , Gravidez , RNA Viral/sangue , Sexo sem Proteção/estatística & dados numéricos , Adulto Jovem
13.
AIDS Behav ; 16(5): 1260-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21901486

RESUMO

Exclusive breastfeeding has been associated with a reduced risk of late vertical HIV transmission as compared to an infant diet composed of breast milk mixed with supplemental foods or liquids. Hypothesized mechanisms include increased infectivity of breast milk from mothers who practice mixed breastfeeding (MBF), or mechanisms such as increased gastrointestinal permeability in the infant caused by mixed feeding. It has been proposed that MBF may result in subclinical mastitis and higher breast milk HIV titers. However, little is known about the relationship between feeding strategy and breast milk viral load. We measured the HIV-1 concentration in breast milk in a sub-cohort of women enrolled in a mother-to-child HIV transmission prevention trial (the "Mashi" study). We report no observed relationship between MBF and measured breast milk viral RNA load. Our findings suggest that the increased transmission risk associated with higher breast milk HIV-1 RNA during MBF is unlikely.


Assuntos
Aleitamento Materno , Soropositividade para HIV/transmissão , Fórmulas Infantis , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Mastite/prevenção & controle , Leite Humano/virologia , RNA Viral/análise , Adulto , Botsuana/epidemiologia , Estudos de Coortes , Feminino , Soropositividade para HIV/virologia , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Mastite/epidemiologia , Gravidez , Carga Viral
14.
Antimicrob Agents Chemother ; 55(5): 2146-53, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21402856

RESUMO

Single-dose nevirapine (NVP) is quite effective in preventing transmission of the human immunodeficiency virus (HIV) from mother to child; however, many women develop resistance to NVP in this setting. Comparing outcomes of clinical studies reveals an increased amount of resistance in subtype C relative to that in other subtypes. This study investigates how nonnucleoside reverse transcriptase inhibitor (NNRTI) drug resistance mutations of subtype C affect replication capacity. The 103N, 106A, 106M, 181C, 188C, 188L, and 190A drug resistance mutations were placed in a reverse transcriptase (RT) that matches the consensus subtype C sequence as well as the HXB2 RT, as a subtype B reference. The replicative fitness of each mutant was compared with that of the wild type in a head-to-head competition assay. The 106A mutant of subtype C would not grow in the competition assay, making it the weakest virus tested. The effect of the 106M mutation was weaker than those of the 181C and 188C mutations in the consensus C RT, but in subtype B, this difference was not seen. To see if the 106A mutation in a different subtype C background would have a different replicative profile, the same NNRTI resistance mutations were added to the MJ4 RT, a reference subtype C molecular clone. In the context of MJ4 RT, the 106A mutant was not the only mutant that showed poor replicative fitness; the 106M, 188C, and 190A mutants also failed to replicate. These results suggest that NNRTIs may be a cost-effective alternative for salvage therapy if deleterious mutations are present in a subtype C setting.


Assuntos
HIV/efeitos dos fármacos , HIV/genética , Inibidores da Transcriptase Reversa/farmacologia , Linhagem Celular , Farmacorresistência Viral/genética , Humanos , Mutagênese , Mutação , Reação em Cadeia da Polimerase , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
16.
J Med Virol ; 83(10): 1689-95, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21837784

RESUMO

Human papillomaviruses (HPV) constitute one of the most prevalent sexually transmitted infections and are the etiological agents for invasive cervical cancer, the predominant cancer among women in Botswana. However, the prevalence of HPV genotypes in Botswana has yet to be reported. One hundred thirty-nine endocervical swabs were taken at baseline from HIV-1 infected, HSV-2 seropositive women enrolled in a longitudinal cohort study designed to assess the influence of herpes simplex virus-2 (HSV-2) infection on genital tract shedding of HIV-1. Extracted DNA was evaluated for the presence of low-risk and high-risk HPV using the Roche Linear Array. Genotyping identified HPV in 95 of 139 women of which 61/95 were infected with high-risk HPV and 56/95 with low-risk HPV. The median number of genotypes was 2 (IQR: 1-4). The most prevalent HPV genotype in HIV-infected women was HPV 58. Abnormal cervical cytology was detected in 87/127 women and was associated with contemporaneous HPV infection (RR = 1.43, 95% CI: 1.05-1.93; P = 0.02). HPV prevalence was high among HIV-infected women with infection by multiple genotypes being widespread. The associations attributed to specific oncogenic HPV subtypes and cervical squamous intraepithelial lesions presented here provide critical information to inform future vaccine policy within Botswana.


Assuntos
Alphapapillomavirus/genética , Infecções por HIV/complicações , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Displasia do Colo do Útero/virologia , Adulto , Alphapapillomavirus/classificação , Botsuana/epidemiologia , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Estudos de Coortes , DNA Viral/genética , Feminino , Genótipo , Herpes Genital/complicações , Herpesvirus Humano 2/imunologia , Humanos , Estudos Longitudinais , Displasia do Colo do Útero/epidemiologia
17.
Commun Biol ; 4(1): 227, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33603155

RESUMO

Sensitive and reproducible diagnostics are fundamental to containing the spread of existing and emerging pathogens. Despite the reliance of clinical virology on qPCR, technical challenges persist that compromise their reliability for sustainable epidemic containment as sequence instability in probe-binding regions produces false-negative results. We systematically violated canonical qPCR design principles to develop a Pan-Degenerate Amplification and Adaptation (PANDAA), a point mutation assay that mitigates the impact of sequence variation on probe-based qPCR performance. Using HIV-1 as a model system, we optimized and validated PANDAA to detect HIV drug resistance mutations (DRMs). Ultra-degenerate primers with 3' termini overlapping the probe-binding site adapt the target through site-directed mutagenesis during qPCR to replace DRM-proximal sequence variation. PANDAA-quantified DRMs present at frequency ≥5% (2 h from nucleic acid to result) with a sensitivity and specificity of 96.9% and 97.5%, respectively. PANDAA is an innovative advancement with applicability to any pathogen where target-proximal genetic variability hinders diagnostic development.


Assuntos
Primers do DNA , DNA Viral/genética , Farmacorresistência Viral/genética , Infecções por HIV/virologia , HIV-1/genética , Mutação Puntual , Reação em Cadeia da Polimerase , Virologia/métodos , Fármacos Anti-HIV/uso terapêutico , Combinação Efavirenz, Emtricitabina, Fumarato de Tenofovir Desoproxila/uso terapêutico , Genótipo , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Reprodutibilidade dos Testes
18.
AIDS Res Hum Retroviruses ; 37(1): 16-23, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32935556

RESUMO

Although antiretroviral therapy (ART) effectively suppresses HIV replication, the latent reservoir remains the barrier to HIV eradication. It remains unknown whether long-term ART impacts levels of inducible replication-competent provirus. To address this knowledge gap, we assessed the proviral reservoir in HIV-1 perinatally infected adolescents having received ART for >13 years. We recruited 15 vertically infected adolescents living with HIV in Botswana. Historical viral load, CD4+ T cell count, and treatment data were retrieved from their outpatient medical records. Inducible replication-competent proviruses from cryopreserved peripheral blood mononuclear cells were quantified using a TZM-bl based assay (TZA). Total proviral DNA copies were quantified using droplet digital PCR. The mean age of study participants was 16 years (standard deviation = 0.7) and median CD4+ T cell count at enrollment was 784 [interquartile range (IQR) = 728.8-1,288] cells/mm3. Median age at ART initiation was 8 (IQR = 6-12) months. Fourteen (93%) participants had HIV-1 RNA <400 copies/mL at the time of enrollment in the study. A median of 19 (IQR = 18-27) HIV-1 RNA measurements were available per participant. Six (40%) participants displayed viral suppression at all clinic visits since initiating ART, whereas the remaining 9 (60%) had one or more clinic visits with detectable HIV-1 RNA. The median inducible replication-competent provirus count was 7.4 infectious units per million cells (IQR = 6.7-19.2), and did not differ significantly by either complete or incomplete viral suppression (7.2 vs. 7.4, p = .86), or by age at ART initiation (7.4 if <12 months, 11.2 if >12 months, p = .85). The median total HIV DNA count was 129.1 copies per million cells (IQR = 18.9-212.3). Our data suggest that long-term ART initiated within the 1st year in perinatally infected infants did not eliminate proviral DNA or inducible replication-competent proviruses.


Assuntos
Infecções por HIV , HIV-1 , Adolescente , Botsuana , Linfócitos T CD4-Positivos , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Leucócitos Mononucleares , Provírus/genética , Carga Viral
19.
J Virol ; 83(9): 4051-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19225005

RESUMO

In order to understand the impact of zidovudine resistance and thymidine analog mutations (TAMs) on subtype C human immunodeficiency virus type 1, we created mutants in subtype C reverse transcriptase (RT). The subtype B RT was placed in a subtype C backbone to act as a control. Mutants and wild-type (WT) virus were competed in a head-to-head competition assay to determine how different clones grew in the same culture. Different viruses were distinguished by sequence tags in nef and a quantitative-PCR assay. The 67N and 70R accessory mutations gave an advantage over the WT in subtype C, but these mutations in subtype B had replication capacities similar to that of the WT. Of the triple mutants examined, the TAM-1 types, 41L210W215Y, were the most fit in both subtypes, but only in subtype C was the replication capacity the same as that of the WT. The TAM-2 mutants, 67N70R215F, had the slowest replication in both clones. The mixed TAM pathway mutant, 67N70R215Y, in subtype C had a significant advantage over the TAM-2 mutant, but this was not seen in subtype B. When the WT viruses were competed with each other, the subtype B RT had enhanced replication relative to subtype C. The increased capacities of the 67N and 70R mutations may indicate that there will be greater transmitted resistance and persistence in a subtype C setting than what is known for subtype B.


Assuntos
Farmacorresistência Bacteriana/efeitos dos fármacos , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Timidina/análogos & derivados , Timidina/farmacologia , Replicação Viral/efeitos dos fármacos , Células Cultivadas , HIV-1/classificação , Humanos , Mutação/genética , DNA Polimerase Dirigida por RNA/genética , DNA Polimerase Dirigida por RNA/metabolismo , Timidina/química
20.
J Virol ; 83(6): 2460-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19109381

RESUMO

Cytotoxic-T-lymphocyte (CTL) escape mutations in human immunodeficiency viruses encode amino acid substitutions in positions that disrupt CTL targeting, thereby increasing virus survival and conferring a relative fitness benefit. However, it is now clear that CTL escape mutations can also confer a fitness cost, and there is increasing evidence to suggest that in some cases, e.g., escape from HLA-B*57/B*5801-restricted responses, the costs to the escape virus may affect the clinical course of infection. To quantify the magnitude of the costs of HLA-B*57/B*5801 escape, a highly sensitive dual-infection assay that uses synonymous nucleotide sequence tags to quantify viral relative replication capacity (RRC) was developed. We then asked whether such CTL escape mutations had an impact equivalent to that seen for a benchmark mutation, the M184V antiretroviral drug resistance mutation of reverse transcriptase (RRC(V184) = 0.86). To answer the question, the RRCs were quantified for escape mutations in three immunodominant HLA-B*57/B*5801 epitopes in capsid: A146P in IW9 (RRC(P146) = 0.91), A163G in KF11 (RRC(G163) = 0.89), and T242N in TW10 (RRC(N242) = 0.86). Individually, the impact of the escape mutations on RRC was comparable to that of M184V, while coexpression of the mutations resulted in substantial further reductions, with the maximum impact observed for the triple mutant (RRC(P146-G163-N242) = 0.62). By comparison to M184V, the magnitude of the reductions in RRC caused by the escape mutations, particularly when coexpressed, suggests that the costs of escape are sufficient to affect in vivo viral dynamics and may thus play a role in the protective effect associated with HLA-B*57/B*5801.


Assuntos
Proteínas do Capsídeo/imunologia , Epitopos/imunologia , HIV-1/fisiologia , Antígenos HLA-B/imunologia , Mutação de Sentido Incorreto , Linfócitos T Citotóxicos/imunologia , Replicação Viral , Substituição de Aminoácidos/imunologia , Proteínas do Capsídeo/genética , Linhagem Celular , Epitopos/genética , HIV-1/genética , HIV-1/imunologia , Humanos
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