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Find video protocols related to scientific articles indexed in Pubmed.
Maternal HIV status associated with under-five mortality in rural northern Malawi: A prospective cohort study.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 10-17-2014
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Under-five mortality is decreasing but with little change in neonatal mortality rates. We examined the effect of maternal HIV-status on under-five mortality and cause of death since widespread availability of antiretroviral therapy in rural Malawi.
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A robust SNP barcode for typing Mycobacterium tuberculosis complex strains.
Nat Commun
PUBLISHED: 09-01-2014
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Strain-specific genomic diversity in the Mycobacterium tuberculosis complex (MTBC) is an important factor in pathogenesis that may affect virulence, transmissibility, host response and emergence of drug resistance. Several systems have been proposed to classify MTBC strains into distinct lineages and families. Here, we investigate single-nucleotide polymorphisms (SNPs) as robust (stable) markers of genetic variation for phylogenetic analysis. We identify ~92 k SNP across a global collection of 1,601 genomes. The SNP-based phylogeny is consistent with the gold-standard regions of difference (RD) classification system. Of the ~7 k strain-specific SNPs identified, 62 markers are proposed to discriminate known circulating strains. This SNP-based barcode is the first to cover all main lineages, and classifies a greater number of sublineages than current alternatives. It may be used to classify clinical isolates to evaluate tools to control the disease, including therapeutics and vaccines whose effectiveness may vary by strain type.
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Coreceptor usage, diversity, and divergence in drug-naive and drug-exposed individuals from Malawi, infected with HIV-1 subtype C for more than 20 years.
AIDS Res. Hum. Retroviruses
PUBLISHED: 07-29-2014
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There are few cohorts of individuals who have survived infection with HIV-1 for more than 20 years, reported and followed in the literature, and even fewer from Africa. Here we present data on a cohort of subtype C-infected individuals from rural northern Malawi. By sequencing multiple clones from long-term survivors at different time points, and using multiple genotyping approaches, we show that 5 of the 11 individuals are predicted as CXCR4 using (by ?3/5 predictors) but only one individual is predicted as CXCR4 using by all five algorithms. Using any one genotyping approach overestimates the number of predicted CXCR4 sequences. Patterns of diversity and divergence were variable between the HIV-1 long-term survivors with some individuals showing very small amounts of variation and change, and others showing a greater amount; both patterns are consistent with what has been described in the literature.
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Improved retention of patients starting antiretroviral treatment in Karonga District, northern Malawi, 2005-2012.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 07-01-2014
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Patient retention in antiretroviral therapy (ART) programs remains a major challenge in sub-Saharan Africa. We examined whether and why retention in ART care has changed with increasing access.
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Isoniazid plus antiretroviral therapy to prevent tuberculosis: a randomised double-blind, placebo-controlled trial.
Lancet
PUBLISHED: 05-13-2014
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Antiretroviral therapy reduces the risk of tuberculosis, but tuberculosis is more common in people with HIV than in people without HIV. We aimed to assess the effect of isoniazid preventive therapy on the risk of tuberculosis in people infected with HIV-1 concurrently receiving antiretroviral therapy.
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Uptake of prevention of mother-to-child-transmission using Option B+ in northern rural Malawi: a retrospective cohort study.
Sex Transm Infect
PUBLISHED: 04-08-2014
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To identify points of dropout on the pathway from offering HIV testing to maintenance on antiretroviral therapy (ART), following the introduction of the Option B+ policy for pregnant women in Malawi (lifelong ART for HIV-positive mothers and 6?weeks nevirapine for the infants), a retrospective cohort study within a demographic surveillance system in northern Malawi. Women living in the demographic surveillance system who initiated antenatal care (ANC) between July 2011 (date of policy change) and January 2013, were eligible for inclusion. Women who consented were interviewed at home about their health facility attendance and care since pregnancy, including antenatal clinic (ANC) visits, delivery and postpartum care. Women's reports, patient-held health records and clinic health records were manually linked to ascertain service use. Among 395 women, 86% had tested for HIV before the pregnancy, 90% tested or re-tested at the ANC visit, and <1% had never tested. Among 53 mothers known to be HIV-positive before attending ANC, 15 (28%) were already on ART prior to pregnancy. Ten women tested HIV-positive for the first time during pregnancy. Of the 47 HIV-positive mothers not already on ART, 26/47 (55%) started treatment during pregnancy. All but five women who started ART were still on treatment at the time of study interview. HIV testing was almost universal and most women who initiated ART were retained in care. However, nearly half of eligible pregnant women not on ART at the start of ANC had not taken up the invitation to initiate (lifelong) ART by the time of delivery, leaving their infants potentially HIV-exposed.
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Strengthening the Reporting of Molecular Epidemiology for Infectious Diseases (STROME-ID): an extension of the STROBE statement.
Lancet Infect Dis
PUBLISHED: 03-14-2014
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Molecular data are now widely used in epidemiological studies to investigate the transmission, distribution, biology, and diversity of pathogens. Our objective was to establish recommendations to support good scientific reporting of molecular epidemiological studies to encourage authors to consider specific threats to valid inference. The statement Strengthening the Reporting of Molecular Epidemiology for Infectious Diseases (STROME-ID) builds upon the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) initiative. The STROME-ID statement was developed by a working group of epidemiologists, statisticians, bioinformaticians, virologists, and microbiologists with expertise in control of infection and communicable diseases. The statement focuses on issues relating to the reporting of epidemiological studies of infectious diseases using molecular data that were not addressed by STROBE. STROME-ID addresses terminology, measures of genetic diversity within pathogen populations, laboratory methods, sample collection, use of molecular markers, molecular clocks, timeframe, multiple-strain infections, non-independence of infectious-disease data, missing data, ascertainment bias, consistency between molecular and epidemiological data, and ethical considerations with respect to infectious-disease research. In total, 20 items were added to the 22 item STROBE checklist. When used, the STROME-ID recommendations should advance the quality and transparency of scientific reporting, with clear benefits for evidence reviews and health-policy decision making.
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Pre-treatment loss to follow-up in tuberculosis patients in low- and lower-middle-income countries and high-burden countries: a systematic review and meta-analysis.
Bull. World Health Organ.
PUBLISHED: 03-14-2014
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To assess the magnitude of loss to follow-up in smear- or culture-positive tuberculosis patients before treatment initiation and outcomes among patients who were traced.
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The effect of HIV and antiretroviral therapy on characteristics of pulmonary tuberculosis in northern Malawi: a cross-sectional study.
BMC Infect. Dis.
PUBLISHED: 02-19-2014
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HIV infection reduces the likelihood that individuals with pulmonary tuberculosis are smear positive and that they have cavitatory disease. Antiretroviral therapy (ART) may shift the pattern of disease to be more similar to that of HIV negative patients. This would aid diagnosis--which often depends on sputum smears--but would also increase infectiousness. We assessed the effect of HIV and ART on smear positivity and cavitatory disease in laboratory-confirmed pulmonary TB patients.
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PolyTB: a genomic variation map for Mycobacterium tuberculosis.
Tuberculosis (Edinb)
PUBLISHED: 02-08-2014
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Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) is the second major cause of death from an infectious disease worldwide. Recent advances in DNA sequencing are leading to the ability to generate whole genome information in clinical isolates of M. tuberculosis complex (MTBC). The identification of informative genetic variants such as phylogenetic markers and those associated with drug resistance or virulence will help barcode Mtb in the context of epidemiological, diagnostic and clinical studies. Mtb genomic datasets are increasingly available as raw sequences, which are potentially difficult and computer intensive to process, and compare across studies. Here we have processed the raw sequence data (>1500 isolates, eight studies) to compile a catalogue of SNPs (n = 74,039, 63% non-synonymous, 51.1% in more than one isolate, i.e. non-private), small indels (n = 4810) and larger structural variants (n = 800). We have developed the PolyTB web-based tool (http://pathogenseq.lshtm.ac.uk/polytb) to visualise the resulting variation and important meta-data (e.g. in silico inferred strain-types, location) within geographical map and phylogenetic views. This resource will allow researchers to identify polymorphisms within candidate genes of interest, as well as examine the genomic diversity and distribution of strains. PolyTB source code is freely available to researchers wishing to develop similar tools for their pathogen of interest.
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Earlier menarche is associated with a higher prevalence of Herpes simplex type-2 (HSV-2) in young women in rural Malawi.
Elife
PUBLISHED: 01-30-2014
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Remarkably little is known about associations between age at menarche and sexually transmitted infections, although girls with earlier menarche tend to have earlier sexual debut and school drop-out, so an association might be expected. In a population-based survey of >3000 women aged 15-30 in northern Malawi we show that those with earlier menarche had earlier sexual debut, earlier marriage and were more often Herpes simplex type-2 (HSV-2) positive. Compared to those with menarche aged <14, the age-adjusted odds ratios for HSV-2 were 0.89 (95%CI 0.71-1.1), 0.71 (0.57-0.89) and 0.69 (0.54-0.89) for menarche aged 14, 15 and 16+ respectively. This association persisted after adjusting for socio-economic factors, including schooling, and for sexual behaviour. No such association was seen with HIV infection, which is much less common and less uniformly distributed than HSV-2 in this population. The extra vulnerability of girls with earlier menarche needs to be recognised. DOI: http://dx.doi.org/10.7554/eLife.01604.001.
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Measuring causes of adult mortality in rural northern Malawi over a decade of change.
Glob Health Action
PUBLISHED: 01-01-2014
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Verbal autopsy could be more widely used if interpretation by computer algorithm could be relied on. We assessed how InterVA-4 results compared with clinician review in diagnosing HIV/AIDS-related deaths over the period of antiretroviral (ART) roll-out.
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Underestimation of HIV prevalence in surveys when some people already know their status, and ways to reduce the bias.
AIDS
PUBLISHED: 06-14-2013
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To quantify refusal bias due to prior HIV testing, and its effect on HIV prevalence estimates, in general-population surveys.
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Control of (multi)drug resistance and tuberculosis incidence over 23 years in the context of a well-supported tuberculosis programme in rural Malawi.
PLoS ONE
PUBLISHED: 01-31-2013
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The rise in tuberculosis (TB) incidence following generalized HIV epidemics can overwhelm TB control programmes in resource-limited settings, sometimes accompanied by rising rates of drug resistance. This has led to claims that DOTS-based TB control has failed in such settings. However, few studies have described the effect of a sustained and well-supported DOTS programme on TB incidence and drug resistance over a long period. We present long-term trends in incidence and drug resistance in rural Malawi.
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Characterizing the emergence and persistence of drug resistant mutations in HIV-1 subtype C infections using 454 ultra deep pyrosequencing.
BMC Infect. Dis.
PUBLISHED: 01-28-2013
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The role of HIV-1 RNA in the emergence of resistance to antiretroviral therapies (ARTs) is well documented while less is known about the role of historical viruses stored in the proviral DNA. The primary focus of this work was to characterize the genetic diversity and evolution of HIV drug resistant variants in an individuals provirus during antiretroviral therapy using next generation sequencing.
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Association between Socioeconomic Position and Tuberculosis in a Large Population-Based Study in Rural Malawi.
PLoS ONE
PUBLISHED: 01-01-2013
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There is increasing interest in social structural interventions for tuberculosis. The association between poverty and tuberculosis is well established in many settings, but less clear in rural Africa. In Karonga District, Malawi, we found an association between higher socioeconomic status and tuberculosis from 1986-1996, independent of HIV status and other factors.
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Attempting to explain heterogeneous HIV epidemics in sub-Saharan Africa: potential role of historical changes in risk behaviour and male circumcision.
Sex Transm Infect
PUBLISHED: 09-16-2011
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A key conclusion of the Four Cities Study, carried out to explore reasons for heterogeneity in the HIV epidemic between two cities in sub-Saharan Africa with relatively low prevalence (Cotonou and Yaoundé) and two with high prevalence (Kisumu and Ndola), was that differences in biological cofactors outweighed differences in sexual risk behaviours. The authors explore an alternative hypothesis, that risk behaviours were historically higher in the high-prevalence cities. They also investigate the effects of different prevalence of male circumcision on the HIV epidemics in the four cities.
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Antiretroviral treatment cohort analysis using time-updated CD4 counts: assessment of bias with different analytic methods.
PLoS ONE
PUBLISHED: 09-02-2011
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Survival analysis using time-updated CD4+ counts during antiretroviral therapy is frequently employed to determine risk of clinical events. The time-point when the CD4+ count is assumed to change potentially biases effect estimates but methods used to estimate this are infrequently reported.
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HIV type 1 mutational patterns in HIV type 1 subtype C-infected long-term survivors in Karonga District Malawi: further analysis and correction.
AIDS Res. Hum. Retroviruses
PUBLISHED: 08-30-2011
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Here we present new sequence data from HIV-1 subtype C-infected long-term survivors (LTS) from Karonga District, Malawi. Gag and env sequence data were produced from nine individuals each of whom has been HIV-1 positive for more than 20 years. We show that the three amino acid deletion in gag p17 previously described from these LTS is not real and was a result of an alignment error. We find that the use of dried blood spots for DNA-based studies is limited after storage for 20 years. We also show some unlikely amino acid changes in env C2-V3 in LTS over time and different patterns of genetic divergence among LTS. Although no clear association between mutations and survival could be shown, amino acid changes that are present in more than one LTS may, in the future, be shown to be important.
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Predictive value of interferon-? release assays for incident active tuberculosis: a systematic review and meta-analysis.
Lancet Infect Dis
PUBLISHED: 08-16-2011
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We aimed to assess whether interferon-? release assays (IGRAs) can predict the development of active tuberculosis and whether the predictive ability of these tests is better than that of the tuberculin skin test (TST).
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Reverse transcriptase drug resistance mutations in HIV-1 subtype C infected patients on ART in Karonga District, Malawi.
AIDS Res Ther
PUBLISHED: 06-22-2011
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Drug resistance testing before initiation of, or during, antiretroviral therapy (ART) is not routinely performed in resource-limited settings. High levels of viral resistance circulating within the population will have impact on treatment programs by increasing the chances of transmission of resistant strains and treatment failure. Here, we investigate Drug Resistance Mutations (DRMs) from blood samples obtained at regular intervals from patients on ART (Baseline-22 months) in Karonga District, Malawi. One hundred and forty nine reverse transcriptase (RT) consensus sequences were obtained via nested PCR and automated sequencing from blood samples collected at three-month intervals from 75 HIV-1 subtype C infected individuals in the ART programme.
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Assessing the validity of sexual behaviour reports in a whole population survey in rural Malawi.
PLoS ONE
PUBLISHED: 03-08-2011
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Sexual behaviour surveys are widely used, but under-reporting of particular risk behaviours is common, especially by women. Surveys in whole populations provide an unusual opportunity to understand the extent and nature of such under-reporting.
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Missed opportunities in TB diagnosis: a TB process-based performance review tool to evaluate and improve clinical care.
BMC Public Health
PUBLISHED: 02-22-2011
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Traditional tuberculosis (TB) treatment outcome measures, such as cure rate, do not provide insight into the underlying reasons for missing clinical targets. We evaluated a TB Process-Based Performance Review (TB-PBPR) tool, developed to identify "missed opportunities" for timely and accurate diagnosis of TB. The tool enables performance assessment at the level of process and quality of care.
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Unnatural deaths in South African platinum miners, 1992-2008.
PLoS ONE
PUBLISHED: 01-21-2011
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The mortality rate from unnatural deaths for South Africa is nearly double the world average. Reliable data are limited by inaccurate and incomplete ascertainment of specific causes of unnatural death. This study describes trends in causes of unnatural death between 1992 and 2008 in a cohort of South African miners.
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Combining qualitative and quantitative evidence to determine factors leading to late presentation for antiretroviral therapy in Malawi.
PLoS ONE
PUBLISHED: 01-14-2011
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Treatment seeking delays among people living with HIV have adverse consequences for outcome. Gender differences in treatment outcomes have been observed in sub-Saharan Africa.
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High accuracy of home-based community rapid HIV testing in rural Malawi.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 12-15-2010
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To assess the performance of rapid HIV antibody tests when used as part of a home-based community wide counseling and testing strategy in northern Malawi.
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The effect of HIV infection on time off work in a large cohort of gold miners with known dates of seroconversion.
Occup Environ Med
PUBLISHED: 11-28-2010
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To estimate the effect of HIV infection on time off work. To provide baseline estimates for economic and actuarial models, and for evaluations of ART and other workplace interventions.
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Molecular detection of mixed infections of Mycobacterium tuberculosis strains in sputum samples from patients in Karonga District, Malawi.
J. Clin. Microbiol.
PUBLISHED: 10-20-2010
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The occurrence of mixed infections of Mycobacterium tuberculosis is no longer disputed. However, their frequency, and the impact they may have on our understanding of tuberculosis (TB) pathogenesis and epidemiology, remains undetermined. Most previous studies of frequency applied genotyping techniques to cultured M. tuberculosis isolates and found mixed infections to be rare. PCR-based techniques may be more sensitive for detecting multiple M. tuberculosis strains and can be applied to sputum. To date, one study in South Africa has used a PCR approach and suggested that mixed infection could be common. We investigated mixed infections in northern Malawi using two lineage-specific PCR assays targeting the Latin American-Mediterranean (LAM) and Beijing lineages. Compared with spoligotyping, the specificity and sensitivity of both assays was 100%. From 160 culture-positive sputa, mixed LAM and non-LAM strains were detected in 4 sputa belonging to 2 (2.8%) patients. Both patients were HIV positive, with no history of TB. Cultured isolates from both patients showed only LAM by PCR and spoligotyping. In a set of 377 cultured isolates, 4 were mixed LAM and non-LAM. Only one showed evidence of more than one M. tuberculosis strain using IS6110-based restriction fragment length polymorphism (IS6110-RFLP) and spoligotyping analyses. Corresponding sputa for the 4 isolates were unavailable. Mixed Beijing and non-Beijing strains were not detected in this study. Mixed infections appear to be rare in our setting and are unlikely to affect findings based on DNA fingerprinting data. Molecular methods, which avoid the selective nature of culture and target distinct strains, are well suited to detection of mixed infections.
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Drug resistance mutations in drug-naive HIV type 1 subtype C-infected individuals from rural Malawi.
AIDS Res. Hum. Retroviruses
PUBLISHED: 10-15-2010
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In this preliminary study we show that in 2008, 3 years after antiretroviral therapy was introduced into the Karonga District, Malawi, a greater than expected number of drug-naive individuals have been infected with HIV-1 subtype C virus harboring major and minor drug resistance mutations (DRMs). From a sample size of 40 reverse transcriptase (RT) consensus sequences from drug-naive individuals we found five showing NRTI and four showing NNRTI mutations with one individual showing both. From 29 protease consensus sequences, again from drug-naive individuals, we found evidence of minor DRMs in three. Additional major and minor DRMs were found in clonal sequences from a number of individuals that were not present in the original consensus sequences. This clearly illustrates the importance of sequencing multiple HIV-1 variants from individuals to fully assess drug resistance.
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Age at menarche, schooling, and sexual debut in northern Malawi.
PLoS ONE
PUBLISHED: 09-23-2010
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Age at sexual debut is a key behavioural indicator used in HIV behavioural surveillance. Early age at menarche may precipitate early sex through perceived readiness for sex, or through school drop-out, but this is rarely studied. We investigated trends and circumstances of sexual debut in relation to schooling and age at menarche.
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Child sexual abuse and links to HIV and orphanhood in urban Zimbabwe.
J Epidemiol Community Health
PUBLISHED: 07-13-2010
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Evidence of a link between sexual violence and HIV is growing; however, studies among children are scarce. The authors sought to characterise child sexual abuse in Harare, Zimbabwe, and explore its links with HIV and orphanhood.
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Population-level reduction in adult mortality after extension of free anti-retroviral therapy provision into rural areas in northern Malawi.
PLoS ONE
PUBLISHED: 07-06-2010
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Four studies from sub-Saharan Africa have found a substantial population-level effect of ART provision on adult mortality. It is important to see if the impact changes with time since the start of treatment scale-up, and as treatment moves to smaller clinics.
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Changes in Mycobacterium tuberculosis genotype families over 20 years in a population-based study in Northern Malawi.
PLoS ONE
PUBLISHED: 05-18-2010
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Despite increasing interest in possible differences in virulence and transmissibility between different genotypes of M. tuberculosis, very little is known about how genotypes within a population change over decades, or about relationships to HIV infection.
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What happens to ART-eligible patients who do not start ART? Dropout between screening and ART initiation: a cohort study in Karonga, Malawi.
BMC Public Health
PUBLISHED: 04-30-2010
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Routine ART programme statistics generally only provide information about individuals who start treatment. We aimed to investigate the outcome of those who are eligible but do not start ART in the Malawi programme, factors associated with this dropout, and reasons for not starting treatment, in a prospective cohort study.
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Tuberculosis and survival of HIV-infected individuals by time since seroconversion.
AIDS
PUBLISHED: 03-20-2010
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In a cohort of 1950 HIV-positive men with known dates of HIV seroconversion, 399 developed tuberculosis. Mortality rates following tuberculosis were greatly increased (hazard ratio, adjusted for age at seroconversion, 4.7, 95% confidence interval 3.7-6.1), and this ratio was similar at different times following seroconversion. Overall mortality was similar to that in western seroconverter cohorts with much lower rates of tuberculosis, suggesting that tuberculosis is more a marker of HIV progression than a cause of it.
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Child mortality in rural Malawi: HIV closes the survival gap between the socio-economic strata.
PLoS ONE
PUBLISHED: 03-15-2010
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As HIV-related deaths increase in a population the usual association between low socioeconomic status and child mortality may change, particularly as death rates from other causes decline.
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Declining child mortality in northern Malawi despite high rates of infection with HIV.
Bull. World Health Organ.
PUBLISHED: 03-01-2010
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To determine whether routine surveys, such as the Demographic and Health Surveys (DHS), have underestimated child mortality in Malawi.
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High rates of recurrence in HIV-infected and HIV-uninfected patients with tuberculosis.
J. Infect. Dis.
PUBLISHED: 02-04-2010
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The rate of recurrent tuberculosis disease due to reinfection, compared with the incidence of new tuberculosis, in those with and without HIV infection is not known.
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Yield of HIV-associated tuberculosis during intensified case finding in resource-limited settings: a systematic review and meta-analysis.
Lancet Infect Dis
PUBLISHED: 02-02-2010
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Intensified case finding is the regular screening for evidence of tuberculosis in people infected with HIV, at high risk of HIV, or living in congregate settings. We systematically reviewed studies of intensified case finding published between January, 1994, and April, 2009. In 78 eligible studies, the number of people with tuberculosis detected during intensified case finding varied substantially between countries and target groups of patients. Median prevalence of newly diagnosed tuberculosis was 0.7% in population-based surveys, 2.2% in contact-tracing studies, 2.3% in mines, 2.3% in programmes preventing mother-to-child transmission of HIV, 2.5% in prisons, 8.2% in medical and antiretroviral treatment clinics, and 8.5% in voluntary counselling and testing services. Metaregression analysis of studies that included only people with HIV showed that for each increment in national prevalence of tuberculosis of 100 cases per 100 000 population, intensified case finding identified an additional one case per 100 screened individuals (p=0.03). Microbiological sputum examination of all individuals without prior selection by symptom screening yielded an additional four cases per 100 individuals screened (p=0.05). Data on the use of serial screening, treatment outcomes in actively identified cases of tuberculosis, and cost-effectiveness, however, were lacking. Concerted action is needed to develop intensified case finding as an important method for control of tuberculosis.
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A systematic review and meta-analysis of molecular epidemiological studies of tuberculosis: development of a new tool to aid interpretation.
Trop. Med. Int. Health
PUBLISHED: 08-26-2009
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The proportion of tuberculosis cases in a population that are clustered (i.e. share identical strains of Mycobacterium tuberculosis) reflects ongoing M. tuberculosis transmission. It varies markedly, but it is unclear how much of this variation reflects measurable differences in study design, setting and the patient population. We aimed to assess the relative impact of these factors and develop a tool to improve interpretation of the proportion clustered from an individual study.
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Population-level effect of potential HSV2 prophylactic vaccines on HIV incidence in sub-Saharan Africa.
Vaccine
PUBLISHED: 03-28-2009
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Herpes simplex virus type-2 (HSV2) infection increases HIV transmission. We explore the impact of a potential prophylactic HSV2 vaccination on HIV incidence in Africa using STDSIM an individual-based model. A campaign that achieved 70% coverage over 5 years with a vaccine that reduced susceptibility to HSV2 acquisition and HSV2 reactivation by 75% for 10 years, reduced HIV incidence by 30-40% after 20 years (range 4-66%). Over 20 years, in most scenarios fewer than 100 vaccinations were required to avert one HIV infection. HSV2 vaccines could have a substantial impact on HIV incidence. Intensified efforts are needed to develop an effective HSV2 vaccine.
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Is education the link between orphanhood and HIV/HSV-2 risk among female adolescents in urban Zimbabwe?
Soc Sci Med
PUBLISHED: 03-19-2009
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As the population of orphans grows in AIDS-affected settings, recent studies describe a heightened risk of HIV and sexual risk behaviours among adolescent orphans compared to their non-orphaned peers. This study explores the role of education in explaining the excess sexual risk previously documented among unmarried female orphans in urban Zimbabwe. School attendance and attainment were assessed by type of orphanhood, and for their association with markers of sexual risk (HIV and/or HSV-2 infection) among 743 participants drawn from a random sample of 15-19-year-old girls identified in a cross-sectional survey in Highfield, Harare, in 2004. Multivariable logistic regression was used to assess the role of educational status in explaining the higher prevalence of adverse sexual outcomes among unmarried orphans compared to non-orphans, adjusting for possible confounders. Double orphans had significantly lower educational attendance and attainment than non-orphans. Maternal orphans had higher odds of school drop-out, although this association disappeared when adjusted for recent mobility. Educational status was strongly associated with HIV/HSV-2 risk, but explained only a small part of double orphans sexual risk and did not explain the HIV/HSV-2 risk of maternal and paternal orphans. High overall levels of secondary school participation and school fee assistance provided to vulnerable families may have reduced the schooling disparities between orphans and non-orphans in Highfield. However, further efforts are needed to rectify the schooling inequities that persist, while additional research is needed to identify other socio-economic and emotional factors driving orphans sexual risk so that prevention and support programmes can meet the needs of this growing population.
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HIV and the risk of tuberculosis due to recent transmission over 12 years in Karonga District, Malawi.
Trans. R. Soc. Trop. Med. Hyg.
PUBLISHED: 03-06-2009
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Tuberculosis (TB) patients with strains common to other recent cases (clustering) suggest recent transmission. HIV status and age may affect proportions clustered. We investigated TB clustering by HIV and age in a population-based study in Malawi. Among 746 patients, HIV infection increased the proportion clustered. Sex-period-adjusted odds ratios for the association of HIV and clustering were 1.26 (95% CI 0.4-4.1) for ages 15-25 years, 1.40 (0.9-2.3) for 25-50 years and 10.44 (2.3-47.9) for >50 years and remained stable over two periods examined. These results suggest that HIV increases the proportion of TB due to recent transmission in the elderly.
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Fertility intentions and use of contraception among monogamous couples in northern Malawi in the context of HIV testing: a cross-sectional analysis.
PLoS ONE
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Knowledge of HIV status may influence fertility desires of married men and women. There is little knowledge about the importance of this influence among monogamously married couples and how knowledge of HIV status influences use of contraception among these couples.
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Monitoring the impact of decentralised chronic care services on patient travel time in rural Africa--methods and results in Northern Malawi.
Int J Health Geogr
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Decentralised health services form a key part of chronic care strategies in resource-limited settings by reducing the distance between patient and clinic and thereby the time and costs involved in travelling. However, few tools exist to evaluate the impact of decentralisation on patient travel time or what proportion of patients attend their nearest clinic. Here we develop methods to monitor changes in travel time, using data from the antiretroviral therapy (ART) roll-out in a rural district in North Malawi.
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Effect of antiretroviral therapy on the diagnostic accuracy of symptom screening for intensified tuberculosis case finding in a South African HIV clinic.
Clin. Infect. Dis.
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Current symptom screening algorithms for intensified tuberculosis case finding or prior to isoniazid preventive therapy (IPT) in patients infected with human immunodeficiency virus (HIV) were derived from antiretroviral-naive cohorts. There is a need to validate screening algorithms in patients on antiretroviral therapy (ART).
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The impact of HIV and ART on recurrent tuberculosis in a sub-Saharan setting.
AIDS
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To estimate the impact of antiretroviral therapy (ART) on the incidence of recurrent tuberculosis (TB) in an African population.
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Adult mortality and probable cause of death in rural northern Malawi in the era of HIV treatment.
Trop. Med. Int. Health
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Developing countries are undergoing demographic transition with a shift from high mortality caused by communicable diseases (CD) to lower mortality rates caused by non-communicable diseases (NCD). HIV/AIDS has disrupted this trend in sub-Saharan Africa. However, in recent years, HIV-associated mortality has been reduced with the introduction of widely available antiretroviral therapy (ART). Side effects of ART may lead to increased risk of cardiovascular diseases, raising the prospects of an accelerated transition towards NCD as the primary cause of death. We report population-based data to investigate changes in cause of death owing to NCD during the first 4 years after introduction of HIV treatment.
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The impact of HIV, an antiretroviral programme and tuberculosis on mortality in South African platinum miners, 1992-2010.
PLoS ONE
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HIV and tuberculosis (TB) are the most common causes of death in South Africa. Antiretroviral therapy (ART) programmes should have had an impact on mortality rates. This study describes the impact of HIV, a Wellness (HIV/ART) programme and TB on population-wide trends in mortality and causes of death among South African platinum miners, from before the HIV epidemic into the ART era.
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Profile: the Karonga Health and Demographic Surveillance System.
Int J Epidemiol
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The Karonga Health and Demographic Surveillance System (Karonga HDSS) in northern Malawi currently has a population of more than 35?000 individuals under continuous demographic surveillance since completion of a baseline census (2002-2004). The surveillance system collects data on vital events and migration for individuals and for households. It also provides data on cause-specific mortality obtained by verbal autopsy for all age groups, and estimates rates of disease for specific presentations via linkage to clinical facility data. The Karonga HDSS provides a structure for surveys of socio-economic status, HIV sero-prevalence and incidence, sexual behaviour, fertility intentions and a sampling frame for other studies, as well as evaluating the impact of interventions, such as antiretroviral therapy and vaccination programmes. Uniquely, it relies on a network of village informants to report vital events and household moves, and furthermore is linked to an archive of biological samples and data from population surveys and other studies dating back three decades.
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Very early anthropometric changes after antiretroviral therapy predict subsequent survival, in karonga, Malawi.
Open AIDS J
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Antiretroviral (ART) scale-up in Malawi has been achieved on a large scale based mainly on clinical criteria. Simple markers of prognosis are useful, and we investigated the value of very early anthropometric changes in predicting mortality.
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Measuring concurrency: an empirical study of different methods in a large population-based survey and evaluation of the UNAIDS guidelines.
AIDS
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Recent UNAIDS guidelines recommend measuring concurrency 6 months before the interview date, based on overlapping partnership dates. This has theoretical advantages, but little is known about how well it can be measured in practice.
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Clinical predictors cannot replace biological predictors in HIV-2 infection in a community setting in West Africa.
Int. J. Infect. Dis.
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To identify clinical predictors of mortality in HIV-2-infected individuals that may be used in place of CD4 count or plasma viral load (PVL) to guide treatment management in resource-limited settings.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.