Effect of population viral load on prospective HIV incidence in a hyperendemic rural African community.
Ontology highlight
ABSTRACT:
SUBMITTER: Tanser F
PROVIDER: S-EPMC6435884 | biostudies-literature | 2017 Dec
REPOSITORIES: biostudies-literature
Publications
Effect of population viral load on prospective HIV incidence in a hyperendemic rural African community.
Tanser Frank F Vandormael Alain A Cuadros Diego D Phillips Andrew N AN de Oliveira Tulio T de Oliveira Tulio T Tomita Andrew A Bärnighausen Till T Pillay Deenan D
Science translational medicine 20171201 420
Monitoring HIV population viral load (PVL) has been advocated as an important means of inferring HIV transmission potential and predicting the future rate of new HIV infections (HIV incidence) in a particular community. However, the relationship between PVL measures and directly measured HIV incidence has not been quantified in any setting and, most importantly, in a hyperendemic sub-Saharan African setting. We assessed this relationship using one of Africa's largest population-based prospective ...[more]
Similar Datasets
Project description:BACKGROUND:Undiagnosed HIV infections could undermine efforts to reverse the global AIDS epidemic by 2030. In this study, we estimated the percentage of HIV-positive persons who remain undiagnosed within a hyperendemic South African community. METHODS:The data come from a population-based surveillance system located in the Umkhanyakude district of the northern KwaZulu-Natal province, South Africa. We annually tested 38?661 adults for HIV between 2005 and 2016. Using the HIV-positive test results of 12?039 (31%) participants, we then back-calculated the incidence of infection and derived the number of undiagnosed cases from this result. RESULTS:The percentage of undiagnosed HIV cases decreased from 29.3% in 2005 to 15.8% in 2011. During this period, however, approximately 50% of the participants refused to test for HIV, which lengthened the average time from infection to diagnosis. Consequently, the percentage of undiagnosed HIV cases reversed direction and steadily increased from 16.1% to 18.9% over the 2012-2016 period. CONCLUSIONS:Results from this hyperendemic South African setting show that the HIV testing rate is low, with long infection times, and an unsatisfactorily high percentage of undiagnosed cases. A high level of repeat HIV testing is needed to minimise the time from infection to diagnosis if the global AIDS epidemic is to be reversed within the next two decades.
| S-EPMC6340103 | biostudies-literature
Project description:BACKGROUND:HIV incidence is the best measure of treatment-programme effectiveness, but its measurement is difficult and expensive. The concept of community viral load as a modifiable driver of new HIV infections has attracted substantial attention. We set out to compare several measures of community viral load and antiretroviral therapy (ART) coverage as correlates of HIV incidence in high-risk populations. METHODS:We analysed data from a sample of people who inject drugs and men who have sex with men, who were participants of the baseline assessment of a cluster-randomised trial in progress across 22 cities in India (ClinicalTrials.gov number NCT01686750). We recruited the study population by use of respondent-driven sampling and did the baseline assessment at 27 community-based sites (12 for men who have sex with men and 15 for people who inject drugs). We estimated HIV incidence with a multiassay algorithm and calculated five community-based measures of HIV control: mean log10 HIV RNA in participants with HIV in a community either engaged in care (in-care viral load), aware of their status but not necessarily in care (aware viral load), or all HIV-positive individuals whether they were aware, in care, or not (population viral load); participants with HIV in a community with HIV RNA more than 150 copies per mL (prevalence of viraemia); and the proportion of participants with HIV who self-reported ART use in the previous 30 days (population ART coverage). All participants were tested for HIV, with additional testing in HIV-positive individuals. We assessed correlations between the measures and HIV incidence with Spearman correlation coefficients and linear regression analysis. FINDINGS:Between Oct 1, 2012, and Dec 19, 2013, we recruited 26,503 participants, 12,022 men who have sex with men and 14,481 people who inject drugs. Median incidence of HIV was 0·87% (IQR 0·40-1·17) in men who have sex with men and 1·43% (0·60-4·00) in people who inject drugs. Prevalence of viraemia was more strongly correlated with HIV incidence (correlation 0·81, 95% CI 0·62-0·91; p<0·0001) than all other measures, although correlation was significant with aware viral load (0·59, 0·27-0·79; p=0·001), population viral load (0·51, 0·16-0·74; p=0·007), and population ART coverage (-0·54, -0·76 to -0·20; p=0·004). In-care viral load was not correlated with HIV incidence (0·29, -0·10 to 0·60; p=0·14). With regression analysis, we estimated that to reduce HIV incidence by 1 percentage point in a community, prevalence of viraemia would need to be reduced by 4·34%, and ART use in HIV-positive individuals would need to increase by 19·5%. INTERPRETATION:Prevalence of viraemia had the strongest correlation with HIV incidence in this sample and might be a useful measure of the effectiveness of a treatment programme. FUNDING:US National Institutes of Health, Elton John AIDS Foundation.
| S-EPMC4863069 | biostudies-literature
Project description:BackgroundAd hoc assumptions about the unobserved infection event, which is known only to occur between the latest-negative and earliest-positive test dates, can lead to biased HIV incidence rate estimates. Using a G-imputation approach, we infer the infection dates from covariate data to estimate the HIV incidence rate in a hyper-endemic South African setting.MethodsA large demographic surveillance system has annually tested a cohort of HIV-uninfected participants living in the KwaZulu-Natal province. Using this data, we estimated a cumulative baseline hazard function and the effects of time-dependent covariates on the interval censored infection dates. For each HIV-positive participant in the cohort, we derived a cumulative distribution function and sampled multiple infection dates conditional on the unique covariate values. We right censored the data at the imputed dates, calculated the annual HIV incidence rate per 100 person-years, and used Rubin's rules to obtain the 95% confidence intervals.ResultsA total of 20,011 uninfected individuals with a repeat HIV test participated in the incidence cohort between 2005 and 2018. We observed 2,603 infections per 58,769 person-years of follow-up among women and 845 infections per 41,178 person-years of follow-up among men. Conditional on age and circumcision status (men only), the female HIV incidence rate declined by 25%, from 5.0 to 3.7 infections per 100 person-years between 2014 and 2018. During this period, the HIV incidence rate among men declined from 2.1 to 1.1 infections per 100 person-years-a reduction of 49%. We observed similar reductions in male and female HIV incidence conditional on condom-use, marital status, urban residential status, migration history, and the HIV prevalence in the surrounding community.ConclusionWe have followed participants in one of the world's largest and longest running HIV cohorts to estimate long-term trends in the population-wide incidence of infection. Using a G-imputation approach, we present further evidence for HIV incidence rate declines in this hyper-endemic South African setting.
| S-EPMC7409400 | biostudies-literature
Project description:BACKGROUND:Targeting combination HIV interventions to locations and populations with high HIV burden is a global priority, but the impact of these strategies on HIV incidence is unclear. We assessed the impact of combination HIV interventions on HIV incidence in four HIV-hyperendemic communities in Uganda. METHODS:We did an open population-based cohort study of people aged 15-49 years residing in four fishing communities on Lake Victoria. The communities were surveyed five times to collect self-reported demographic, behavioural, and service-uptake data. Free HIV testing was provided at each interview, with referral to combination HIV intervention services as appropriate. From November, 2011, combination HIV intervention services were rapidly expanded in these geographical areas. We evaluated trends in HIV testing coverage among all participants, circumcision coverage among male participants, antiretroviral therapy (ART) coverage and HIV viral load among HIV-positive participants, and sexual behaviours and HIV incidence among HIV-negative participants. FINDINGS:From Nov 4, 2011, to Aug 16, 2017, data were collected from five surveys. Overall, 8942 participants contributed 20?721 person-visits; 4619 (52%) of 8942 participants were male. HIV prevalence was 41% (1598 of 3870) in the 2011-12 baseline survey and declined to 37% (1740 of 4738) at the final survey (p<0·0001). 3222 participants who were HIV-negative at baseline, and who had at least one repeat visit, contributed 9477 person-years of follow-up, and 230 incident HIV infections occurred. From the first survey in 2011-12 to the last survey in 2016-17, HIV testing coverage increased from 68% (2613 of 3870) to 96% (4526 of 4738; p<0·0001); male circumcision coverage increased from 35% (698 of 2011) to 65% (1630 of 2525; p<0·0001); ART coverage increased from 16% (254 of 1598) to 82% (1420 of 1740; p<0·0001); and population HIV viral load suppression in all HIV-positive participants increased from 34% (546 of 1596) to 80% (1383 of 1734; p<0·0001). Risky sexual behaviours did not decrease over this period. HIV incidence decreased from 3·43 per 100 person-years (95% CI 2·45-4·67) in 2011-12 to 1·59 per 100 person-years (95% CI 1·19-2·07) in 2016-17; adjusted incidence rate ratio (IRR) 0·52 (95% CI 0·34-0·79). Declines in HIV incidence were similar among men (adjusted IRR 0·53, 95% CI 0·30-0·93) and women (0·51, 0·27-0·96). The risk of incident HIV infection was lower in circumcised men than in uncircumcised men (0·46, 0·32-0·67). INTERPRETATION:Rapid expansion of combination HIV interventions in HIV-hyperendemic fishing communities is feasible and could have a substantial impact on HIV incidence. However, incidence remains higher than HIV epidemic control targets, and additional efforts will be needed to achieve this global health priority. FUNDING:The National Institute of Mental Health, the National Institute of Allergy and Infectious Diseases, the National Institute of Child Health and Development, the National Cancer Institute, the National Institute for Allergy and Infectious Diseases Division of Intramural Research, Centers for Disease Control and Prevention Uganda, Karolinska Institutet, and the Johns Hopkins University Center for AIDS Research.
| S-EPMC6832692 | biostudies-literature
Project description:OBJECTIVE:African-American women are more likely than other women in the United States to experience poor HIV-related health; HIV stigma may contribute to these outcomes. This study assessed the relationship between HIV stigma and viral load, over time, among a sample of African-American women receiving treatment for HIV, and explored social support and depressive symptoms as mediators. DESIGN:Secondary analysis of longitudinal data. METHODS:Data came from a randomized trial of an intervention to reduce HIV stigma among African-American women in HIV care in Chicago, Illinois and Birmingham, Alabama. Sociodemographic and psychosocial data were collected at up to six study visits over 14 months. Viral loads were extracted from medical records during the study period. Generalized linear mixed effects models were used to estimate associations among overall, internalized, and enacted HIV stigma and viral load over time. Mediation analyses were used to estimate indirect effects via social support and depressive symptoms. RESULTS:Data from 234 women were analyzed. Overall HIV stigma was significantly associated with subsequent viral load (adjusted ??=?0.24, P?=?0.005). Both between-subject (adjusted ??=?0.74, P?<?0.001) and within-subject (adjusted ??=?0.34, P?=?0.005) differences in enacted stigma were associated with viral load. Neither social support nor depressive symptoms were statistically significant mediators. CONCLUSION:Ongoing experiences of HIV stigmatization may contribute to increased viral load among African-American women in primary HIV care. Interventions should aim to alleviate the consequences of stigma experienced by patients and prevent future stigmatization.
| S-EPMC6621603 | biostudies-literature
Project description:BACKGROUNDAntiretroviral therapy (ART) was highly efficacious in preventing human immunodeficiency virus (HIV) transmission in stable serodiscordant couples in the HPTN-052 study, a resource-intensive randomized controlled trial with near-perfect ART adherence and mutual HIV status disclosure among all participating couples. However, minimal evidence exists of the effectiveness of ART in preventing HIV acquisition in stable serodiscordant couples in "real-life" population-based settings in hyperendemic communities of sub-Saharan Africa, where health systems are typically resource-poor and overburdened, adherence to ART is often low, and partners commonly do not disclose their HIV status to each other.METHODSData arose from a population-based open cohort in KwaZulu-Natal, South Africa. A total of 17 016 HIV-uninfected individuals present between January 2005 and December 2013 were included. Interval-censored time-updated proportional hazards regression was used to assess how the ART status affected HIV transmission risk in stable serodiscordant relationships.RESULTSWe observed 1619 HIV seroconversions in 17 016 individuals, over 60 349 person-years follow-up time. During the follow-up period, 1846 individuals had an HIV-uninfected and 196 had an HIV-infected stable partner HIV incidence was 3.8/100 person-years (PY) among individuals with an HIV-infected partner (95% confidence interval [CI], 2.3-5.6), 1.4/100 PY (.4-3.5) among those with HIV-infected partners receiving ART, and 5.6/100 PY (3.5-8.4) among those with HIV-infected partners not receiving ART. Use of ART was associated with a 77% decrease in HIV acquisition risk among serodiscordant couples (adjusted hazard ratio, 0.23; 95% CI, .07-.80).CONCLUSIONSART initiation was associated with a very large reduction in HIV acquisition in serodiscordant couples in rural KwaZulu-Natal. However, this "real-life" effect was substantially lower than the effect observed in the HPTN-052 trial. To eliminate HIV transmission in serodiscordant couples, additional prevention interventions are probably needed.
| S-EPMC4967606 | biostudies-literature
Project description: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 SPVL?4.75 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.
| S-EPMC4063664 | biostudies-literature
Project description:BACKGROUND:Infections cause about one fifth of the estimated 2.7 million annual neonatal deaths worldwide. Population-based data on burden and risk factors of neonatal infections are lacking in developing countries, which are required for the appropriate design of effective preventive and therapeutic interventions in resource-poor settings. METHODS:We used data from a community-based cluster-randomized trial conducted to evaluate the impact of two umbilical cord cleansing regimens with chlorhexidine solution on neonatal mortality and morbidity in a rural area of Sylhet District in Bangladesh. Newborns were assessed four times in the first 9 days of life by trained community health workers (CHWs) using a WHO IMCI-like clinical algorithm. Cumulative incidence of the first episode of infections in the first 9 days of life was estimated using survival analysis technique accounting for survival bias and competing risk of death before the occurrence of infection. A multivariable generalized estimating equation log-binomial regression model was used to identify factors independently associated with infections. RESULTS:Between 2007 and 2009, 30,267 newborns who received at least one postnatal assessment visit by a CHW within the first 9 days of life were included in this study. Cumulative incidence of infections in the first 9 days of life was 14.5% (95% CI 14.1-14.9%). Significant risk factors included previous child death in the family [RR 1.10 (95% CI 1.02-1.19)]; overcrowding [RR 1.14 (95% CI 1.04-1.25)]; home delivery [RR 1.86 (95% CI 1.58-2.19)]; unclean cord care [RR 1.15 (95% CI 1.03-1.28)]; multiple births [RR 1.34 (95% CI 1.15-1.56)]; low birth weight [reference: ??2500 g, RR (95% CI) for <?1500, 1500-1999, and 2000-2499 g were 4.69 (4.01-5.48), 2.15 (1.92-2.42), and 1.15 (1.07-1.25) respectively]; and birth asphyxia [RR 1.65 (1.51-1.81)]. Higher pregnancy order lowered the risk of infections in the study population [compared to first pregnancy, RR (95% CI) for second, third, and ? fourth pregnancy babies were 0.93 (0.85-1.02), 0.88 (0.79-0.97), and 0.79 (0.71-0.87), respectively]. CONCLUSION:Neonatal infections and associated deaths can be reduced by identifying and following up high-risk mothers and newborns and promoting facility delivery and clean cord care in resource-poor countries like Bangladesh where the burden of clinically ascertained neonatal infections is high. Further research is needed to measure the burden of infections in the entire neonatal period, particularly in the second fortnight and its association with essential newborn care. TRIAL REGISTRATION:NCT00434408 . Registered February 9, 2007.
| S-EPMC5845215 | biostudies-literature
Project description:Assays for classifying HIV infections as 'recent' or 'nonrecent' for incidence surveillance fail to simultaneously achieve large mean durations of 'recent' infection (MDRIs) and low 'false-recent' rates (FRRs), particularly in virally suppressed persons. The potential for optimizing recent infection testing algorithms (RITAs), by introducing viral load criteria and tuning thresholds used to dichotomize quantitative measures, is explored.The Consortium for the Evaluation and Performance of HIV Incidence Assays characterized over 2000 possible RITAs constructed from seven assays (Limiting Antigen, BED, Less-sensitive Vitros, Vitros Avidity, BioRad Avidity, Architect Avidity, and Geenius) applied to 2500 diverse specimens.MDRIs were estimated using regression, and FRRs as observed 'recent' proportions, in various specimen sets. Context-specific FRRs were estimated for hypothetical scenarios. FRRs were made directly comparable by constructing RITAs with the same MDRI through the tuning of thresholds. RITA utility was summarized by the precision of incidence estimation.All assays produce high FRRs among treated patients and elite controllers (10-80%). Viral load testing reduces FRRs, but diminishes MDRIs. Context-specific FRRs vary substantially by scenario - BioRad Avidity and Limiting Antigen provided the lowest FRRs and highest incidence precision in scenarios considered.The introduction of a low viral load threshold provides crucial improvements in RITAs. However, it does not eliminate nonzero FRRs, and MDRIs must be consistently estimated. The tuning of thresholds is essential for comparing and optimizing the use of assays. The translation of directly measured FRRs into context-specific FRRs critically affects their magnitudes and our understanding of the utility of assays.
| S-EPMC5024345 | biostudies-literature
Project description:OBJECTIVE:In a recent genome-wide association study of HIV-1-infected individuals in the Euro-CHAVI cohort, viral load set-point was strongly associated with genotypes defined by two single nucleotide polymorphisms (SNPs) (rs9264942 and rs2395029) within the human major histocompatibility complex (MHC) region on chromosome 6. We attempted to confirm this finding in African-Americans and to address whether these SNPs are in linkage disequilibrium with human leukocyte antigen (HLA) class I alleles that mediate innate and adaptive immunity. DESIGN:Our analyses relied on 121 African-American adolescents with chronic HIV-1 infection and quarterly immunological and virological outcome measures in the absence of therapy. METHODS:PCR-based techniques were used to genotype two SNPs along with HLA class I alleles. Their associations with HIV-1 viral load set-point and longitudinal CD4+ and CD8+CD38+ T cell counts were tested in univariate and multivariable models. RESULTS:The CC genotype at rs9264942 was associated with reduced viral load, but not with immunological outcomes or category of disease control. Consistent associations of favorable virologic outcomes were observed with B*57 (mostly B*5703) but not with rs2395029G allele at the HCP5 locus, which is in absolute linkage disequilibrium with B*5701 (in individuals of European descent), and not B*5703. CONCLUSION:Although rs9264942 and B*57 (but not rs2395029G) are clearly associated with control of viral load set-point among African-Americans, fine-mapping of MHC SNPs in populations of African and European descent should help reveal the causative variants and the underlying functional mechanisms.
| S-EPMC2663898 | biostudies-literature