RESUMO
HIV-1 remains a global health crisis1, highlighting the need to identify new targets for therapies. Here, given the disproportionate HIV-1 burden and marked human genome diversity in Africa2, we assessed the genetic determinants of control of set-point viral load in 3,879 people of African ancestries living with HIV-1 participating in the international collaboration for the genomics of HIV3. We identify a previously undescribed association signal on chromosome 1 where the peak variant associates with an approximately 0.3 log10-transformed copies per ml lower set-point viral load per minor allele copy and is specific to populations of African descent. The top associated variant is intergenic and lies between a long intergenic non-coding RNA (LINC00624) and the coding gene CHD1L, which encodes a helicase that is involved in DNA repair4. Infection assays in iPS cell-derived macrophages and other immortalized cell lines showed increased HIV-1 replication in CHD1L-knockdown and CHD1L-knockout cells. We provide evidence from population genetic studies that Africa-specific genetic variation near CHD1L associates with HIV replication in vivo. Although experimental studies suggest that CHD1L is able to limit HIV infection in some cell types in vitro, further investigation is required to understand the mechanisms underlying our observations, including any potential indirect effects of CHD1L on HIV spread in vivo that our cell-based assays cannot recapitulate.
Assuntos
DNA Helicases , Proteínas de Ligação a DNA , Variação Genética , Infecções por HIV , HIV-1 , Carga Viral , Humanos , Linhagem Celular , DNA Helicases/genética , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Infecções por HIV/genética , HIV-1/crescimento & desenvolvimento , HIV-1/fisiologia , Carga Viral/genética , África , Cromossomos Humanos Par 1/genética , Alelos , RNA Longo não Codificante/genética , Replicação ViralRESUMO
Modern HIV research depends crucially on both viral sequencing and population measurements. To directly link mechanistic biological processes and evolutionary dynamics during HIV infection, we developed multiple within-host phylodynamic models of HIV primary infection for comparative validation against viral load and evolutionary dynamics data. The optimal model of primary infection required no positive selection, suggesting that the host adaptive immune system reduces viral load but surprisingly does not drive observed viral evolution. Rather, the fitness (infectivity) of mutant variants is drawn from an exponential distribution in which most variants are slightly less infectious than their parents (nearly neutral evolution). This distribution was not largely different from either in vivo fitness distributions recorded beyond primary infection or in vitro distributions that are observed without adaptive immunity, suggesting the intrinsic viral fitness distribution may drive evolution. Simulated phylogenetic trees also agree with independent data and illuminate how phylogenetic inference must consider viral and immune-cell population dynamics to gain accurate mechanistic insights.
Assuntos
Adaptação Fisiológica/genética , Infecções por HIV/virologia , HIV-1/genética , Filogenia , Carga Viral , Aptidão Genética , Humanos , Modelos Genéticos , Mutação , Reprodutibilidade dos TestesRESUMO
Clusters of genetically similar infections suggest rapid transmission and may indicate priorities for public health action or reveal underlying epidemiological processes. However, clusters often require user-defined thresholds and are sensitive to non-epidemiological factors, such as non-random sampling. Consequently the ideal threshold for public health applications varies substantially across settings. Here, we show a method which selects optimal thresholds for phylogenetic (subset tree) clustering based on population. We evaluated this method on HIV-1 pol datasets (n = 14, 221 sequences) from four sites in USA (Tennessee, Washington), Canada (Northern Alberta) and China (Beijing). Clusters were defined by tips descending from an ancestral node (with a minimum bootstrap support of 95%) through a series of branches, each with a length below a given threshold. Next, we used pplacer to graft new cases to the fixed tree by maximum likelihood. We evaluated the effect of varying branch-length thresholds on cluster growth as a count outcome by fitting two Poisson regression models: a null model that predicts growth from cluster size, and an alternative model that includes mean collection date as an additional covariate. The alternative model was favoured by AIC across most thresholds, with optimal (greatest difference in AIC) thresholds ranging 0.007-0.013 across sites. The range of optimal thresholds was more variable when re-sampling 80% of the data by location (IQR 0.008 - 0.016, n = 100 replicates). Our results use prospective phylogenetic cluster growth and suggest that there is more variation in effective thresholds for public health than those typically used in clustering studies.
Assuntos
Infecções por HIV , HIV-1 , Humanos , HIV-1/genética , Filogenia , Estudos Prospectivos , Saúde Pública , Infecções por HIV/epidemiologia , Análise por ConglomeradosRESUMO
BACKGROUND: In sub-Saharan Africa many people who inject drugs (PWID) are living with undiagnosed or untreated HIV and experience high levels of poverty and conditions that can contribute to worse outcomes from SARS-CoV-2 infection. Identifying the burden of SARS-CoV-2 infection in marginalized populations like PWID may contribute to controlling the pandemic. METHODS: This is a nested cross-sectional study within an ongoing cohort study that recruits PWID living with HIV and their injecting and/or sexual partners at needle and syringe program sites and methadone clinics in Kenya. Blood samples were collected from consenting participants at enrollment to determine SARS-CoV-2 antibodies using a Platellia BioRad SARS-CoV-2 total antibody enzyme-linked immunosorbent assay. Baseline data were collected on HIV status, antiretroviral therapy and methadone adherence. We used logistic regression to identify factors associated with antibody positivity and descriptive statistics to report SARS-CoV-2 antibody prevalence. RESULTS: One thousand participants were enrolled between April and July 2021, of whom 323 (32.3%) were women and 677 (67.7%) were men. Median age of participants was 36 years (interquartile range: 30, 42). SARS-CoV-2 antibody positivity was found in 309 (30.9%) participants. Disruption in obtaining methadone service was reported by 106 (24.3%) of the participants. Men were significantly less likely than women to have SARS-CoV-2 antibodies (adjusted odds ratio [aOR] = 0.68, 95% confidence interval [CI] 0.51, 0.95; p < 0.01) Participants who reported a sexual or injecting partner diagnosed with SARS-CoV-2 were twofold more likely to have SARS-CoV-2 antibodies detected (aOR = 2.21, 95% CI 1.06, 4.58; p < 0.032). Living with HIV was not associated with presence of SARS-CoV-2 antibodies. CONCLUSION: The seroprevalence of SARS-CoV-2 of 30.9% in this cohort suggests high transmission rates within this population. SARS-CoV-2 seroprevalence was similar for people living with and without HIV. A large portion of this population was noted to have had disruption in access to harm reduction services.
Assuntos
COVID-19 , Usuários de Drogas , Infecções por HIV , Abuso de Substâncias por Via Intravenosa , Masculino , Humanos , Feminino , Adulto , Abuso de Substâncias por Via Intravenosa/epidemiologia , Abuso de Substâncias por Via Intravenosa/complicações , SARS-CoV-2 , Estudos Soroepidemiológicos , Estudos de Coortes , Prevalência , Quênia/epidemiologia , Estudos Transversais , Redução do Dano , COVID-19/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/complicações , MetadonaRESUMO
BACKGROUND: In Kenya, violence is common among people who inject drugs (PWID) living with HIV and their sexual and injecting partners and may lead to decreased uptake of HIV services, increased HIV risk behaviors, and increased HIV transmission. Violence is defined as any physical harm, threatened harm, or forced sexual acts inflicted on a person in the past year. Understanding the nature of violence and its correlates among PWID and their partners will inform population-specific public health interventions and policy recommendations. METHODS: This is a cross-sectional study nested in a prospective cohort study conducted in eight public health centers, methadone clinics, and needle syringe programs in Nairobi, Kilifi, and Mombasa counties in Kenya. 3,302 sexual and/or injecting partners of PWID living with HIV were recruited through assisted partner services and participated in the study. Prevalence and correlates of violence were identified using the Wald test and negative binomial regression. RESULTS: Out of 3302 study participants, 1439 (44%) had experienced violence within the past year. Physical violence was the most common form of violence experienced (35%), followed by being threatened (23%) or subjected to sexual violence (7%). In an adjusted analysis, female participants reported higher experiences of sexual violence (prevalence ratio [PR] = 2.46; 95% confidence interval [CI] 1.62, 3.74; p < 0.001) compared to male participants. In adjusted analysis, coastal residents had a higher experience of overall violence (PR = 1.48; 95% CI 1.27, 1.72; p < 0.001) than those living in Nairobi. This regional effect was relatively stronger among the female respondents (pinteraction = 0.025). Participants' sex modified the association between region and experiencing violence after adjusting potential confounding factors. CONCLUSIONS: The study reveals the prevalence of violence among PWID and identifies high-risk sub-groups, including women, specifically for sexual violence, and coastal residents. Tailored interventions addressing their unique needs are essential. A holistic approach that combines violence prevention and response, comprehensive harm reduction, healthcare access, and community support is crucial to address the complex issue of drug use and HIV burden among PWID in Kenya for improved health outcomes.
Assuntos
Usuários de Drogas , Infecções por HIV , Abuso de Substâncias por Via Intravenosa , Masculino , Humanos , Feminino , Estudos Transversais , Abuso de Substâncias por Via Intravenosa/epidemiologia , Prevalência , Quênia/epidemiologia , Estudos Prospectivos , Infecções por HIV/epidemiologia , Violência , Parceiros SexuaisRESUMO
We examined patterns of genetic clustering among individuals diagnosed with HIV between 2010 and 2018 using data from King County, Washington's National HIV Surveillance System. Among 2,371 individuals newly diagnosed with HIV, 231 (10%) experienced unstable housing or were living homeless at the time of diagnosis. Among the 1,658 (70%) people with an available HIV-1 pol gene sequence, 1,071 (65%) were identified to be part of 296 genetic clusters. In our analysis, housing status was not associated with genetic clustering (OR 1.02; 95%CI:0.75,1.39). After adjusting for demographic and behavioral factors, people who were living homeless at HIV diagnosis had 35% lower odds of being identified as part of a genetic cluster (AOR 0.65; 95%CI:0.44,0.95) compared to people with stable housing. Our findings highlight that people experiencing unstable housing are disproportionately burdened by HIV, and that within this population in King County, being in a genetic cluster is predominantly associated with substance use.
Assuntos
Infecções por HIV , Pessoas Mal Alojadas , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Habitação , Humanos , Epidemiologia Molecular , Washington/epidemiologiaRESUMO
BACKGROUND: Persons who inject drugs (PWID) have higher HIV and hepatitis C virus (HCV) seroprevalence than the general population in many parts of sub-Saharan Africa (SSA). The seroprevalences of HIV and HCV are also higher in coastal Kenya than in Nairobi. Understanding drivers of regional HIV and HCV variation among PWID in Kenya may inform population-specific prevention interventions. METHODS: Using a cross-sectional study, we defined HIV and HCV seroprevalence among persons identified as sexual or injecting partners of HIV positive PWID in two regions of Kenya and used logistic regression to identify demographic and behavioral characteristics associated with higher seroprevalence. RESULTS: Among 2386 partners, 469 (19.7%) tested HIV positive and 297(12.4%) tested HCV antibody positive. Partners on the Coast were more likely to live with HIV (seroprevalences: Coast = 23.8%, Nairobi = 17.1%; p < 0.001) and be HCV antibody positive (seroprevalences: Coast = 17.0%, Nairobi = 8.6%; p < 0.001). After adjusting for sex, age, and years injecting and accounting for clustering by site, the higher prevalence of both diseases in the Coast remained significant for HIV (OR 1.68, 95% CI 1.13-2.51) but not for HCV (OR 1.72, 95% CI 0.84-3.74). Compared to those recruited in Nairobi, partners on the Coast were older (Coast = 35 years, Nairobi = 31 years; p < 0.001), more likely to be male (Coast = 77.6%, Nairobi = 61.7%; p < 0.001), to have paid (Coast = 59.2%, Nairobi = 32.8%; p < 0.001) or received (Coast = 44.2%, Nairobi 35.4%; p < 0.001) money for sex, or to have had sex with someone they knew to be HIV positive (Coast 22.0%, Nairobi 10.8%; p < 0.001). Partners who had injected for five or more years had 1.48 times greater odds (95% CI 1.20-1.82) of living with HIV compared to partners who injected less than 5 years and more than twice the odds of HCV (95% CI 1.84-4.11). CONCLUSION: HIV and HCV seroprevalence among sexual and injecting partners of PWID was, respectively, 5 times and > 12 times greater than is reported among the general population in Kenya (4% and < 1%, respectively). Providing resources and education will be crucial to reduce exposure and to maintain the lower needle and equipment sharing that we observed compared to other studies.
Assuntos
Usuários de Drogas , Infecções por HIV , Hepatite C , Preparações Farmacêuticas , Abuso de Substâncias por Via Intravenosa , Estudos Transversais , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Hepacivirus , Hepatite C/epidemiologia , Humanos , Quênia/epidemiologia , Masculino , Prevalência , Assunção de Riscos , Estudos Soroepidemiológicos , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologiaRESUMO
Predominantly heterosexual HIV-1 epidemics like those in sub-Saharan Africa continue to have high HIV incidence in young people. We used a stochastic, agent-based model for age-disparate networks to test the hypothesis that focusing uptake and retention of ART among youth could enhance the efficiency of treatment as prevention (TasP) campaigns. We used the model to identify strategies that reduce incidence to negligible levels (i.e., < 0.1 cases/100 person-years) 20-25 years after initiation of a targeted TasP campaign. The model was parameterized using behavioral, demographic, and clinical data from published papers and national reports. To keep a focus on the underlying age effects we model a generalized heterosexual population with average risks (i.e., no MSM, no PWIDs, no sex workers) and no entry of HIV+ people from other regions. The model assumes that most people (default 95%, range in variant simulations 60-95%) are "linkable"; i.e., could get linked to effective care given sufficient resources. To simplify the accounting, we assume a rapid jump in the number of people receiving treatment at the start of the TasP campaign, followed by a 2% annual increase that continues until all linkable HIV+ people have been treated. Under historical scenarios of CD4-based targeted ART allocation and current policies of untargeted (random) ART allocation, our model predicts that viral replication would need to be suppressed in 60-85% of infected people at the start of the TasP campaign to drive incidence to negligible levels. Under age-based strategies, by contrast, this percentage dropped by 18-54%, depending on the strength of the epidemic and the age target. For our baseline model, targeting those under age 30 halved the number of people who need to be treated. Age-based targeting also minimized total and time-discounted AIDS deaths over 25 years. Age-based targeting yielded benefits without being highly exclusive; in a model in which 60% of infected people were treated, ~87% and ~58% of those initiating therapy during a campaign targeting those <25 and <30 years, respectively, fell outside the target group. Sensitivity analyses revealed that youth-focused TasP is beneficial due to age-related risk factors (e.g. shorter relationship durations), and an age-specific herd immunity (ASHI) effect that protects uninfected adolescents entering the sexually active population. As testing rates increase in response to UNAIDS 90-90-90 goals, efforts to link all young people to care and treatment could contribute enormously to ending the HIV epidemic.
Assuntos
Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Adulto , Fatores Etários , Contagem de Linfócito CD4 , Biologia Computacional , Simulação por Computador , Epidemias/prevenção & controle , Feminino , Infecções por HIV/epidemiologia , HIV-1 , Heterossexualidade , Humanos , Masculino , Fatores Sexuais , Software , Análise de Sistemas , Adulto JovemRESUMO
Background: The prevalence of detectable viremia has previously been used to infer the potential for ongoing human immunodeficiency virus (HIV) transmission. To date, no study has evaluated the longitudinal change in the prevalence of detectable viremia within the HIV-positive community (PDV+) and the entire population (PDVP) using data from a sub-Saharan African setting. Methods: In 2011, 2013, and 2014, we obtained 6752 HIV-positive and 15415 HIV-negative test results from a population-based surveillance system in the KwaZulu-Natal province of South Africa. We quantified the PDV+ as the proportion of the 6752 HIV-positive results with a viral load >1550 copies/mL and the PDVP as the proportion of the 6752 HIV-positive and 15415 HIV-negative results with a viral load >1550 copies/mL. Results: Between 2011 and 2014, the PDV+ decreased by 16.5 percentage points (pp) for women (from 71.8% to 55.3%) and 10.6 pp for men (from 77.8% to 67.2%). However, a steady rise in the overall HIV prevalence, from 26.7% to 32.4%, offset the declines in the PDV+ for both sexes. For women, the PDVP decreased by only 2.1 pp, from 21.3% to 19.2%, but for men, the PDVP actually increased by 1.6 pp, from 14.6% to 16.2%, over the survey period. Conclusions: The PDV+, which is currently being tracked under the UNAIDS 90-90-90 targets, may not be an accurate indicator of the potential for ongoing HIV transmission. There is a critical need for countries to monitor and report the prevalence of detectable viremia among all adults, irrespective of HIV status.
Assuntos
Infecções por HIV/epidemiologia , Soropositividade para HIV , HIV/imunologia , Vigilância da População , Viremia/epidemiologia , Adolescente , Adulto , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/transmissão , Infecções por HIV/virologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , População Rural , Comportamento Sexual , África do Sul/epidemiologia , Carga Viral , Viremia/diagnóstico , Viremia/transmissão , Viremia/virologia , Adulto JovemRESUMO
BACKGROUND: Transmission of human immunodeficiency virus type 1 (HIV-1) drug resistance mutations, particularly that of minority drug-resistant variants, remains poorly understood. Population-based studies suggest that drug-resistant HIV-1 is less transmissible than drug-susceptible viruses. We compared HIV-1 drug-resistant genotypes among partner-pairs in order to assess the likelihood of transmission of drug resistance mutations and investigate the role of minority variants in HIV transmission. METHODS AND FINDINGS: From 1992-2010, 340 persons with primary HIV-1 infection and their partners were enrolled into observational research studies at the University of Washington Primary Infection Clinic (UWPIC). Out of 50 partner-pairs enrolled, 36 (72%) transmission relationships were confirmed by phylogenetic distance analysis of HIV-1 envelope (env) sequences, and 31 partner-pairs enrolled after 1995 met criteria for this study. Drug resistance mutations in the region of the HIV-1 polymerase gene (pol) that encodes protease and reverse transcriptase were assessed by 454-pyrosequencing. In 25 partner-pairs where the transmission direction could be determined, 12 (48%) transmitters had 1-4 drug resistance mutations (23 total) detected in their HIV-1 populations at a median frequency of 6.0% (IQR 1.5%-98.7%, range 1.0%-99.6%). Of 10 major mutations detected in five transmitters at a frequency >95%, 100% (95% CI 69.2%-100%) were detected in recipients. All of these transmitters were antiretroviral (ARV)-naïve at the time of specimen collection. Fourteen mutations (eight major mutations and six accessory mutations) were detected in nine transmitters at low frequencies (1.0%-11.8%); four of these transmitters had previously received ARV therapy. Two (14% [95% CI 1.8%-42.8%]) G73S accessory mutations were detected in both transmitter and recipient. This number is not significantly different from the number expected based on the observed frequencies of drug-resistant viruses in transmitting partners. Limitations of this study include the small sample size and uncertainties in determining the timing of virus transmission and mutation history. CONCLUSIONS: Drug-resistant majority variants appeared to be commonly transmitted by ARV-naïve participants in our analysis and may contribute significantly to transmitted drug resistance on a population level. When present at low frequency, no major mutation was observed to be shared between partner-pairs; identification of accessory mutations shared within a pair could be due to transmission, laboratory artifact, or apolipoprotein B mRNA-editing enzyme, catalytic polypeptides (APOBECs), and warrants further study.
Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , HIV-1/genética , Mutação , Adulto , Fármacos Anti-HIV/uso terapêutico , Estudos de Coortes , Estudos Transversais , Análise Mutacional de DNA , Feminino , Genótipo , Humanos , Masculino , Filogenia , Parceiros SexuaisRESUMO
PURPOSE OF REVIEW: This review summarizes the use of genetic similarity clusters to understand HIV transmission and inform prevention efforts. RECENT FINDINGS: Recent emphases include the development of real-time cluster identification in order to interrupt transmission chains, the use of clusters to estimate rates of transmission along the HIV care cascade, and the extension of cluster analyses to understand transmission in the generalized epidemics of sub-Saharan Africa. Importantly, this recent empirical work has been accompanied by theoretical work that elucidates the processes that underlie HIV genetic similarity clusters; multiple studies suggest that clusters are not necessarily enriched with individuals with high transmission rates, but rather can reflect variation in sampling times within a population, with individuals sampled early in infection more likely to cluster. Analyses of genetic similarity clusters have great promise to inform HIV epidemiology and prevention. Future emphases should include the collection of additional sequence data from underrepresented populations, such as those in sub-Saharan Africa, and further development and evaluation of clustering methods.
Assuntos
Infecções por HIV/genética , Infecções por HIV/prevenção & controle , África Subsaariana/epidemiologia , Análise por Conglomerados , Epidemias , Predisposição Genética para Doença , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , HumanosRESUMO
Previous genome-wide association studies (GWAS) of HIV-1-infected populations have been underpowered to detect common variants with moderate impact on disease outcome and have not assessed the phenotypic variance explained by genome-wide additive effects. By combining the majority of available genome-wide genotyping data in HIV-infected populations, we tested for association between â¼8 million variants and viral load (HIV RNA copies per milliliter of plasma) in 6,315 individuals of European ancestry. The strongest signal of association was observed in the HLA class I region that was fully explained by independent effects mapping to five variable amino acid positions in the peptide binding grooves of the HLA-B and HLA-A proteins. We observed a second genome-wide significant association signal in the chemokine (C-C motif) receptor (CCR) gene cluster on chromosome 3. Conditional analysis showed that this signal could not be fully attributed to the known protective CCR5Δ32 allele and the risk P1 haplotype, suggesting further causal variants in this region. Heritability analysis demonstrated that common human genetic variation-mostly in the HLA and CCR5 regions-explains 25% of the variability in viral load. This study suggests that analyses in non-European populations and of variant classes not assessed by GWAS should be priorities for the field going forward.
Assuntos
Predisposição Genética para Doença , HIV-1/genética , Interações Hospedeiro-Patógeno/genética , Polimorfismo de Nucleotídeo Único/genética , Carga Viral/genética , Adulto , Alelos , Aminoácidos/genética , Cromossomos Humanos Par 3/genética , Estudo de Associação Genômica Ampla , Antígenos HLA-B/genética , Humanos , Padrões de Herança/genética , Mapeamento Físico do Cromossomo , Receptores CCR5/genéticaRESUMO
Multiple genome-wide association studies (GWAS) have been performed in HIV-1 infected individuals, identifying common genetic influences on viral control and disease course. Similarly, common genetic correlates of acquisition of HIV-1 after exposure have been interrogated using GWAS, although in generally small samples. Under the auspices of the International Collaboration for the Genomics of HIV, we have combined the genome-wide single nucleotide polymorphism (SNP) data collected by 25 cohorts, studies, or institutions on HIV-1 infected individuals and compared them to carefully matched population-level data sets (a list of all collaborators appears in Note S1 in Text S1). After imputation using the 1,000 Genomes Project reference panel, we tested approximately 8 million common DNA variants (SNPs and indels) for association with HIV-1 acquisition in 6,334 infected patients and 7,247 population samples of European ancestry. Initial association testing identified the SNP rs4418214, the C allele of which is known to tag the HLA-B*57:01 and B*27:05 alleles, as genome-wide significant (p = 3.6 × 10⻹¹). However, restricting analysis to individuals with a known date of seroconversion suggested that this association was due to the frailty bias in studies of lethal diseases. Further analyses including testing recessive genetic models, testing for bulk effects of non-genome-wide significant variants, stratifying by sexual or parenteral transmission risk and testing previously reported associations showed no evidence for genetic influence on HIV-1 acquisition (with the exception of CCR5Δ32 homozygosity). Thus, these data suggest that genetic influences on HIV acquisition are either rare or have smaller effects than can be detected by this sample size.
Assuntos
Infecções por HIV/genética , HIV-1/fisiologia , Interações Hospedeiro-Patógeno , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Estudos de Coortes , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Infecções por HIV/virologia , Humanos , População BrancaRESUMO
Trends in HIV virulence have been monitored since the start of the AIDS pandemic, as studying HIV virulence informs our understanding of HIV epidemiology and pathogenesis. Here, we model changes in HIV virulence as a strictly evolutionary process, using set point viral load (SPVL) as a proxy, to make inferences about empirical SPVL trends from longitudinal HIV cohorts. We develop an agent-based epidemic model based on HIV viral load dynamics. The model contains functions for viral load and transmission, SPVL and disease progression, viral load trajectories in multiple stages of infection, and the heritability of SPVL across transmissions. We find that HIV virulence evolves to an intermediate level that balances infectiousness with longer infected lifespans, resulting in an optimal SPVLâ¼4.75 log10 viral RNA copies/mL. Adaptive viral evolution may explain observed HIV virulence trends: our model produces SPVL trends with magnitudes that are broadly similar to empirical trends. With regard to variation among studies in empirical SPVL trends, results from our model suggest that variation may be explained by the specific epidemic context, e.g. the mean SPVL of the founding lineage or the age of the epidemic; or improvements in HIV screening and diagnosis that results in sampling biases. We also use our model to examine trends in community viral load, a population-level measure of HIV viral load that is thought to reflect a population's overall transmission potential. We find that community viral load evolves in association with SPVL, in the absence of prevention programs such as antiretroviral therapy, and that the mean community viral load is not necessarily a strong predictor of HIV incidence.
Assuntos
Epidemias , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/patogenicidade , Modelos Biológicos , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Biologia Computacional , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Humanos , RNA Viral/sangue , Carga Viral , VirulênciaRESUMO
We evaluated the prevalence and correlates of HIV viral nonsuppression and HIV drug resistance (HIV-DR) in a cohort of people who inject drugs living with HIV (PWID-LH) and their sexual and injecting partners living with HIV in Kenya. HIV-DR testing was performed on participants with viral nonsuppression. Of 859 PWID-LH and their partners, 623 (72.5%) were on antiretroviral therapy (ART) ≥4 months and 148/623 (23.8%) were not virally suppressed. Viral nonsuppression was more common among younger participants and those on ART for a shorter duration. Among 122/148 (82.4%) successfully sequenced samples, 55 (45.1%) had detectable major HIV-DR mutations, mainly to non-nucleoside and nucleotide reverse transcriptase inhibitors (NNRTI and NRTI). High levels of HIV-DR among those with viral nonsuppression suggests need for viral load monitoring, adherence counseling, and timely switching to alternate ART regimens in this key population.
RESUMO
BACKGROUND: People who inject drugs are at increased risk of both HIV and hepatitis C virus (HCV) infections but face barriers to testing and engagement in care. Assisted partner services are effective in locating people with HIV but are understudied among people who inject drugs. We assessed whether assisted partner services could be used to find, test for HIV and HCV infections, and link to care the partners of people who inject drugs in Kenya. METHODS: In this prospective study at eight sites offering harm-reduction services in Kenya, we enrolled people aged 18 years or older who inject drugs and were living with HIV (index participants) between Feb 27, 2018, and Nov 1, 2021. Index participants provided information about their sexual and injecting partners (ie, anyone with whom they had had sexual intercourse or injected drugs in the previous 3 years), and then community-embedded peer educators located partners and referred them for enrolment in the study (partner participants). All participants underwent testing for HCV infection, and partner participants also underwent HIV testing. Index and partner participants with HIV but who were not on antiretroviral therapy (ART) were linked with treatment services, and those positive for HCV were linked to treatment with direct-acting antivirals. We calculated the number of index participants whom we needed to interview to identify partner participants with HIV and HCV infection. FINDINGS: We enrolled 989 people living with HIV who inject drugs, who mentioned 4705 sexual or injecting partners. Of these 4705 partners, we enrolled 4597 participants, corresponding to 3323 unique individuals. 597 (18%) partner participants had HIV, of whom 506 (85%) already knew their status. 358 (71%) of those who knew they were HIV positive were virally suppressed. 393 (12%) partner participants were HCV antibody positive, 213 (54%) of whom had viraemia and 104 (26%) of whom knew their antibody status. 1·66 (95% CI 1·53-1·80) index participants had to be interviewed to identify a partner with HIV, and 4·24 (3·75-4·85) had to be interviewed to find a partner living with HIV who was unaware of their HIV status, not on ART, or not virally suppressed. To find a partner seropositive for HCV who did not know their antibody status, 3·47 (3·11-3·91) index participants needed to be interviewed. Among the 331 index and partner participants living with HIV who were not on ART at enrolment, 238 (72%) were taking ART at 6-month follow-up. No adverse events were attributed to study procedures. INTERPRETATION: Use of assisted partner services among people with HIV who inject drugs was safe and identified partners with HIV and HCV infections. Assisted partner services was associated with increased uptake of ART for both index participants and partners. FUNDING: US National Institutes of Health.
Assuntos
Usuários de Drogas , Hepatite C Crônica , Hepatite C , Estados Unidos , Humanos , Hepacivirus , Estudos Prospectivos , Quênia/epidemiologia , Antivirais , Hepatite C/epidemiologiaRESUMO
HIV incidence has been declining in Africa with scale-up of HIV interventions. However, there is limited data on HIV evolutionary trends in African populations with waning epidemics. We evaluated changes in HIV viral diversity and genetic divergence in southern Uganda over a twenty-five-year period spanning the introduction and scale-up of HIV prevention and treatment programs using HIV sequence and survey data from the Rakai Community Cohort Study, an open longitudinal population-based HIV surveillance cohort. Gag (p24) and env (gp41) HIV data were generated from persons living with HIV (PLHIV) in 31 inland semi-urban trading and agrarian communities (1994 to 2018) and four hyperendemic Lake Victoria fishing communities (2011 to 2018) under continuous surveillance. HIV subtype was assigned using the Recombination Identification Program with phylogenetic confirmation. Inter-subtype diversity was estimated using the Shannon diversity index and intra-subtype diversity with the nucleotide diversity and pairwise TN93 genetic distance. Genetic divergence was measured using root-to-tip distance and pairwise TN93 genetic distance analyses. Evolutionary dynamics were assessed among demographic and behavioral sub-groups, including by migration status. 9,931 HIV sequences were available from 4,999 PLHIV, including 3,060 and 1,939 persons residing in inland and fishing communities, respectively. In inland communities, subtype A1 viruses proportionately increased from 14.3% in 1995 to 25.9% in 2017 (p<0.001), while those of subtype D declined from 73.2% in 1995 to 28.2% in 2017 (p<0.001). The proportion of viruses classified as recombinants significantly increased by more than four-fold. Inter-subtype HIV diversity has generally increased. While p24 intra-subtype genetic diversity and divergence leveled off after 2014, diversity and divergence of gp41 increased through 2017. Inter- and intra-subtype viral diversity increased across all population sub-groups, including among individuals with no recent migration history or extra-community sexual partners. This study provides insights into population-level HIV evolutionary dynamics in declining African HIV epidemics following the scale-up of HIV prevention and treatment programs. Continued molecular surveillance may provide a better understanding of the dynamics driving population HIV evolution and yield important insights for epidemic control and vaccine development.
RESUMO
HIV-1 infection is characterized by a chronic activation of the immune system and suppressed function of T lymphocytes. Regulatory CD4+ CD25(high) FoxP3+CD127(low) T cells (Treg) play a key role in both conditions. Here, we show that HIV-1 positive patients have a significant increase of Treg-associated expression of CD39/ENTPD1, an ectoenzyme which in concert with CD73 generates adenosine. We show in vitro that the CD39/adenosine axis is involved in Treg suppression in HIV infection. Treg inhibitory effects are relieved by CD39 down modulation and are reproduced by an adenosine-agonist in accordance with a higher expression of the adenosine A2A receptor on patients' T cells. Notably, the expansion of the Treg CD39+ correlates with the level of immune activation and lower CD4+ counts in HIV-1 infected patients. Finally, in a genetic association study performed in three different cohorts, we identified a CD39 gene polymorphism that was associated with down-modulated CD39 expression and a slower progression to AIDS.
Assuntos
Adenosina/imunologia , Antígenos CD/imunologia , Apirase/imunologia , Infecções por HIV/imunologia , Linfócitos T Reguladores/imunologia , Adenosina/metabolismo , Antígenos CD/metabolismo , Apirase/metabolismo , Biomarcadores/metabolismo , Bulgária/epidemiologia , Proliferação de Células , Células Cultivadas , Progressão da Doença , Regulação para Baixo , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , França/epidemiologia , Expressão Gênica , Infecções por HIV/metabolismo , Infecções por HIV/mortalidade , Humanos , Ativação Linfocitária , Polimorfismo Genético , Receptor A2A de Adenosina/genética , Receptor A2A de Adenosina/metabolismo , Taxa de Sobrevida , Linfócitos T Reguladores/metabolismoRESUMO
INTRODUCTION: The widespread implementation of molecular HIV surveillance (MHS) has resulted in an increased discussion about the ethical, human rights and public health implications of MHS. We narrate our process of pausing our research that uses data collected through MHS in response to these growing concerns and summarize the key lessons we learned through conversations with community members. METHODS: The original study aimed to describe HIV transmission patterns by age and race/ethnicity among men who have sex with men in King County, Washington, by applying probabilistic phylodynamic modelling methods to HIV-1 pol gene sequences collected through MHS. In September 2020, we paused the publication of this research to conduct community engagement: we held two public-facing online presentations, met with a national community coalition that included representatives of networks of people living with HIV, and invited two members of this coalition to provide feedback on our manuscript. During each of these meetings, we shared a brief presentation of our methods and findings and explicitly solicited feedback on the perceived public health benefit and potential harm of our analyses and results. RESULTS: Some community concerns about MHS in public health practice also apply to research using MHS data, namely those related to informed consent, inference of transmission directionality and criminalization. Other critiques were specific to our research study and included feedback about the use of phylogenetic analyses to study assortativity by race/ethnicity and the importance of considering the broader context of stigma and structural racism. We ultimately decided the potential harms of publishing our study-perpetuating racialized stigma about men who have sex with men and eroding the trust between phylogenetics researchers and communities of people living with HIV-outweighed the potential benefits. CONCLUSIONS: HIV phylogenetics research using data collected through MHS data is a powerful scientific technology with the potential to benefit and harm communities of people living with HIV. Addressing criminalization and including people living with HIV in decision-making processes have the potential to meaningfully address community concerns and strengthen the ethical justification for using MHS data in both research and public health practice. We close with specific opportunities for action and advocacy by researchers.