Judith R Glynn

London School of Hygiene and Tropical Medicine, Londinium, England, United Kingdom

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Publications (200)1547.28 Total impact

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    ABSTRACT: Fertility preferences are an essential component of family planning program evaluation; however, doubts about their validity in sub-Saharan Africa exist and little methodological assessment has been carried out. This study investigates prospective fertility intentions in terms of their temporal stability, intensity, degree of spousal agreement, and association with future childbearing in northern Malawi. A total of 5,222 married women participated in the three-round study. The odds of having a child or becoming pregnant within 36 months were 4.2 times higher when both wife and husband wanted a child within three years and 2 times higher when both wanted to wait at least three years, compared with the odds when both wanted to cease childbearing. The influence of husbands' and wives' preferences on subsequent fertility was equal. Compared with the intention to stop, the intention to postpone childbearing was less stable, recorded less spousal agreement, and was much less strongly predictive of fertility. © 2015 The Authors. Studies in Family Planning is published by The Population Council, Inc. on behalf of Wiley Periodicals, Inc.
    Studies in Family Planning 06/2015; 46(2):161-176. DOI:10.1111/j.1728-4465.2015.00022.x
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    ABSTRACT: Mycobacterium tuberculosis drug resistance (DR) challenges effective tuberculosis disease control. Current molecular tests examine limited numbers of mutations, and although whole genome sequencing approaches could fully characterise DR, data complexity has restricted their clinical application. A library (1,325 mutations) predictive of DR for 15 anti-tuberculosis drugs was compiled and validated for 11 of them using genomic-phenotypic data from 792 strains. A rapid online ‘TB-Profiler’ tool was developed to report DR and strain-type profiles directly from raw sequences. Using our DR mutation library, in silico diagnostic accuracy was superior to some commercial diagnostics and alternative databases. The library will facilitate sequence-based drug-susceptibility testing. Electronic supplementary material The online version of this article (doi:10.1186/s13073-015-0164-0) contains supplementary material, which is available to authorized users.
    Genome Medicine 05/2015; 7(1). DOI:10.1186/s13073-015-0164-0
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    ABSTRACT: Background Phylogenetic-based classification of M. tuberculosis and other bacterial genomes is a core analysis for studying evolutionary hypotheses, disease outbreaks and transmission events. Whole genome sequencing is providing new insights into the genomic variation underlying intra- and inter-strain diversity, thereby assisting with the classification and molecular barcoding of the bacteria. One roadblock to strain investigation is the lack of user-interactive solutions to interrogate and visualise variation within a phylogenetic tree setting. Results We have developed a web-based tool called PhyTB (http://pathogenseq.lshtm.ac.uk/phytblive/index.php) to assist phylogenetic tree visualisation and identification of M. tuberculosis clade-informative polymorphism. Variant Call Format files can be uploaded to determine a sample position within the tree. A map view summarises the geographical distribution of alleles and strain-types. The utility of the PhyTB is demonstrated on sequence data from 1,601 M. tuberculosis isolates. Conclusion PhyTB contextualises M. tuberculosis genomic variation within epidemiological, geographical and phylogenic settings. Further tool utility is possible by incorporating large variants and phenotypic data (e.g. drug-resistance profiles), and an assessment of genotype-phenotype associations. Source code is available to develop similar websites for other organisms (http://sourceforge.net/projects/phylotrack).
    BMC Bioinformatics 05/2015; 16(1). DOI:10.1186/s12859-015-0603-3
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    ABSTRACT: People have argued that the benefits of human immunodefi-ciency virus (HIV) testing and counselling are so important that participants in HIV surveys must be given their HIV test results and that individuals who decline to receive their test results should be excluded from participation in such surveys. 1–3 In early attempts at HIV surveillance, there were many logistical issues that complicated the return of test results and few advantages to infected individuals in receiving their test results. 4 Now the situation has changed radically with the widespread roll-out of HIV treatment and care – which not only prolongs life but also reduces sexual and vertical transmission of HIV. 2 We agree that researchers now have an obligation to offer and encourage post-test counselling as part of a research encounter but argue that there are both practical and ethical reasons to allow study participants to opt out of post-test counselling. In African populations with HIV prevalence above 4%, between 30% and 81% of infected men and women have ever been tested for HIV. 5 Those who know they are HIV-positive may be willing to donate blood samples for research purposes but may not want to repeat pre-and post-test counselling. The same may be true of those who feel certain that they are uninfected. Sexually active men and women are encouraged to be tested regularly. Research studies should provide the option for those who arrange to be frequently retested – so-called repeat testers – to be given their test results in a short format and be allowed to opt out of post-test counselling. They should also be prepared for participants who do not wish to collect their test results in any format. All participants – including those who provide blood samples for research but opt out of post-test counselling – can be asked to report their testing histories and testing motives. Importantly, the opt-out provisions we discuss here align with the general principles of research ethics. We agree that there is public health utility in informing people of their HIV status but we think that this should not override the ethics of respect for individual autonomy. Informed consent procedures typically tell willing subjects that they have a right not to answer questions that make them uncomfortable and a right to withdraw from the study at any time without completing all the activities and procedures. Declining to receive a test result is an example of the right of participants to opt out of part of a study. Whether in research or clinical practice, public health utility would be better served through understanding peoples' reasons for not wanting to receive an HIV test result – while informing individuals about all of the available testing and counselling options. Rather than excluding those who decline post-test counselling , we have the obligation to understand the reasons for research participation – and non-participation – better, including attitudes to learning or confirming one's HIV status. Longitudinal studies with repeated HIV testing are particularly well placed to investigate decision-making around HIV testing. The results of such studies could demonstrate whether refusal to participate or receive test results lead to biased estimates of HIV prevalence that weaken the public health utility of the data. 6,7 They could also teach us about why and how people become motivated to be tested 8 and that knowledge could lead to improvements in the design of programmes of HIV testing. ■
    Bulletin of the World Health Organisation 05/2015; 93(5):356-357. DOI:10.2471/BLT.14.135756
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    ABSTRACT: To improve understanding of the factors influencing tuberculosis transmission and the role of pathogen variation, we sequenced all available specimens from patients diagnosed over 15 years in a whole district in Malawi. Mycobacterium tuberculosis lineages were assigned and transmission networks constructed, allowing ≤10 single nucleotide polymorphisms (SNPs) difference. We defined disease as due to recent infection if the network-determined source was within 5 years, and assessed transmissibility from forward transmissions resulting in disease. High-quality sequences were available for 1687 disease episodes (72% of all culture-positive episodes): 66% of patients linked to at least one other patient. The between-patient mutation rate was 0.26 SNPs/year (95% CI 0.21-0.31). We showed striking differences by lineage in the proportion of disease due to recent transmission and in transmissibility (highest for lineage-2 and lowest for lineage-1) that were not confounded by immigration, HIV status or drug resistance. Transmissions resulting in disease decreased markedly over time.
    eLife Sciences 03/2015; 4:e05166. DOI:10.7554/eLife.05166
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    ABSTRACT: Background Tuberculosis (TB) mortality remains high across sub-Saharan Africa despite integration of TB and HIV/ART programmes. To inform programme design and service delivery, we estimated mortality by time from starting TB treatment.Methods Routinely collected data on TB treatment, vital status, and the timing and causes of death, were linked to cardio-respiratory autopsy data, from 1995¿2008, from a cohort of male platinum miners in South Africa. Records were expanded into person-months at risk (pm).Results4162 TB episodes were registered; 3170 men were treated for the first time and 833 men underwent retreatment. Overall, 509 men died, with a case fatality of 12.2% and mortality rate of 2.0/100 pm. Mortality was highest in the first month after starting TB treatment for first (2.3/100 pm) and retreatment episodes (4.8/100 pm). When stratified by HIV status, case fatality was higher in HIV positive men not on ART (first episode 14.0%; retreatment episode 26.2%) and those on ART (12.0%; 22.0%) than men of negative or unknown HIV status (2.6%; 3.6%). Mortality was also highest in the first month for each of these groups. Mortality risk factors included older age, previous TB, HIV, pulmonary TB, and diagnostic uncertainty. The proportion of deaths attributable to TB was consistently overestimated in clinical records versus cardio-respiratory autopsy.Conclusions Programme mortality was highest in those with HIV and during the first month of TB treatment in all groups, and many deaths were not caused by TB. Resource allocation should prioritise TB prevention and accurate earlier diagnosis, recognise the role of HIV, and ensure effective clinical care in the early stages of TB treatment.
    BMC Infectious Diseases 12/2014; 14(1):679. DOI:10.1186/s12879-014-0679-9
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    ABSTRACT: Background. Recurrent tuberculosis is a major health burden and may be due to relapse with the original strain or reinfection with a new strain. Methods. In a population-based study in northern Malawi, patients with tuberculosis diagnosed from 1996 to 2010 were actively followed after the end of treatment. Whole-genome sequencing with approximately 100-fold coverage was performed on all available cultures. Results of IS6110 restriction fragment-length polymorphism analyses were available for cultures performed up to 2008. Results. Based on our data, a difference of ≤10 single-nucleotide polymorphisms (SNPs) was used to define relapse, and a difference of >100 SNPs was used to define reinfection. There was no evidence of mixed infections among those classified as reinfections. Of 1471 patients, 139 had laboratory-confirmed recurrences: 55 had relapse, and 20 had reinfection; for 64 type of recurrence was unclassified. Almost all relapses occurred in the first 2 years. Human immunodeficiency virus infection was associated with reinfection but not relapse. Relapses were associated with isoniazid resistance, treatment before 2007, and lineage-3 strains. We identified several gene variants associated with relapse. Lineage-2 (Beijing) was overrepresented and lineage-1 underrepresented among the reinfecting strains (P = .004). Conclusions. While some of the factors determining recurrence depend on the patient and their treatment, differences in the Mycobacterium tuberculosis genome appear to have a role in both relapse and reinfection.
    The Journal of Infectious Diseases 10/2014; 211(7):1154-1163. DOI:10.1093/infdis/jiu574
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    ABSTRACT: 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.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 10/2014; 68(1). DOI:10.1097/QAI.0000000000000405
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    ABSTRACT: 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 B92k 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 B7k 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.
    Nature Communications 09/2014; 5. DOI:10.1038/ncomms5812
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    ABSTRACT: We assessed the impact on measured burden and outcomes of the revised World Health Organization and Malawi guidelines reclassifying people with single (including 'scanty') positive smears as smear-positive pulmonary tuberculosis cases. In a retrospective cohort in rural Malawi, 567 (34%) of 1670 smear-positive episodes were based on single positive smears (including 176 with scanty smears). Mortality rates and the proportion starting treatment were similar in those with two positive smears or single, non-scanty smears. Those with single scanty smears had higher mortality and a lower proportion starting treatment. The reclassification will increase the reported burden substantially, but should improve treatment access.
    The International Journal of Tuberculosis and Lung Disease 07/2014; 18(7):843-6. DOI:10.5588/ijtld.13.0811
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    ABSTRACT: 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.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 06/2014; DOI:10.1097/QAI.0000000000000252
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    ABSTRACT: 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 four of the eleven individuals are predicted as CXCR4-using (by ≥3/5 predictors) but only one individual is predicted as CXCR4-using by all 5 algorithms. Using any one genotyping approach over-estimates 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, while others show a greater amount; both patterns consistent with what has been described in the literature.
    AIDS Research and Human Retroviruses 06/2014; 30(10). DOI:10.1089/AID.2013.0240
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    ABSTRACT: 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.
    The Lancet 05/2014; 384(9944). DOI:10.1016/S0140-6736(14)60162-8
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    ABSTRACT: Background 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. Design In the Karonga Prevention Study demographic surveillance site in northern Malawi, all deaths are followed by verbal autopsy using a semi-structured questionnaire. Cause of death is assigned by two clinicians with a third as a tie-breaker. The clinician review diagnosis was compared with the InterVA diagnosis using the same questionnaire data, including all adult deaths from late 2002 to 2012. For both methods data on HIV status were used. ART was first available in the district from 2005, and within the demographic surveillance area from 2006. Results There were 1,637 adult deaths, with verbal autopsy data for 1,615. Adult mortality and the proportion of deaths attributable to HIV/AIDS fell dramatically following ART introduction, but for each year the proportion attributed to HIV/AIDS by InterVA was lower than that attributed by clinician review. This was partly explained by the handling of TB cases. Using clinician review as the best available ‘gold standard’, for those aged 15–59, the sensitivity of InterVA for HIV/AIDS deaths was 59% and specificity 88%. Grouping HIV/AIDS/TB sensitivity was 78% and specificity 83%. Sensitivity was lower after widespread ART use. Conclusions InterVA underestimates the proportion of deaths due to HIV/AIDS. Accepting that it is unrealistic to try and differentiate TB and AIDS deaths would improve the estimates. Caution is needed in interpreting trends in causes of death as ART use may affect the performance of the algorithm.
    Global Health Action 04/2014; 7:23621. DOI:10.3402/gha.v7.23621
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    ABSTRACT: 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.
    Sexually transmitted infections 04/2014; 90(4). DOI:10.1136/sextrans-2013-051336
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    ABSTRACT: 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.
    The Lancet Infectious Diseases 03/2014; 14(4). DOI:10.1016/S1473-3099(13)70324-4
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    ABSTRACT: 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. Three sputum samples were collected per pulmonary TB suspect and were examined using microscopy and culture. Chest radiographs were available for a subset of patients as part of another study. The effect of HIV and ART status on sputum smear positivity and lung cavitation were evaluated using multivariable logistic regression. Of 1024 laboratory-confirmed pulmonary TB patients who were identified between January 2005 and December 2011, 766 had HIV and ART status available. Positive sputum smears were significantly more common among HIV negative individuals than HIV positive individuals (adjusted OR = 2.91, 95% CI 1.53 - 5.55). Compared to those HIV positive but not on ART , patients on ART were more likely to be smear positive (adjusted OR = 2.33, 95% CI 1.01 - 5.39) if they had been on ART <= 6 months, but only slightly more likely to be smear positive (adjusted OR = 1.43, 95% CI 0.68 - 2.99) if they were on ART > 6 months. HIV negative patients were more likely than HIV positive patients to have cavitatory disease (adjusted OR = 1.97, 95% CI 1.20 - 3.23). Patients on ART > 6 months had a slight increase in cavitatory disease compared to HIV positive patients not on ART (adjusted OR = 1.68, CI 0.78 - 3.63). HIV infection is associated with less smear positivity and cavitation in pulmonary TB patients. Among HIV positive patients, the use of ART shifts the presentation of disease towards that seen in HIV-negative individuals, which facilitates diagnosis but which also could increase infectiousness.
    BMC Infectious Diseases 02/2014; 14(1):107. DOI:10.1186/1471-2334-14-107
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    ABSTRACT: 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.
    Tuberculosis (Edinburgh, Scotland) 02/2014; 94(3). DOI:10.1016/j.tube.2014.02.005
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    ABSTRACT: 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. Ovid Medline and Global Health databases were searched for studies published between 1994 and January 2013 that described pre-treatment loss to follow-up in patients with smear- or culture-positive tuberculosis in routine national tuberculosis programmes (NTPs) in low- and lower-middle-income countries and in countries with a high burden of tuberculosis. Data on the proportion of patients who did not initiate treatment after their tuberculosis diagnosis were extracted from studies meeting inclusion criteria. Where available, data on causes and outcomes, including initiation of tuberculosis treatment at another facility, were investigated. Heterogeneity and publication bias were assessed and random-effects meta-analyses by subgroup (region) were performed. Twenty-three eligible studies were identified, with a total of 34 706 smear- or culture-positive tuberculosis patients from 14 countries (8 in Africa, 5 in Asia and 1 in the western Pacific). Most studies were retrospective and linked laboratory and treatment registers to identify pre-treatment loss to follow-up. Pre-treatment loss to follow-up varied from 4 to 38% and was common in studies from Africa (random-effects weighted proportion, WP: 18%; 95% confidence interval, CI: 13-22) and Asia (WP: 13%; 95% CI: 10-15). Pre-treatment loss to follow-up, common in most settings, can hinder tuberculosis control efforts. By not counting individuals who are lost to follow-up before treatment when reporting standard programme indicators, NTPs underestimate case detection rates and mortality and overestimate cure rates.
    Bulletin of the World Health Organisation 02/2014; 92(2):126-138. DOI:10.2471/BLT.13.124800
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    ABSTRACT: 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. To investigate the relationship in the same area in 1997-2010. All adults in the district with new laboratory-confirmed tuberculosis were included. They were compared with community controls, selected concurrently and frequency-matched for age, sex and area. 1707 cases and 2678 controls were interviewed (response rates >95%). The odds of TB were increased in those working in the cash compared to subsistence economy (p<0.001), and with better housing (p-trend=0.006), but decreased with increased asset ownership (p-trend=0.003). The associations with occupation and housing were partly mediated by HIV status, but remained significant. Different socioeconomic measures capture different pathways of the association between socioeconomic status and tuberculosis. Subsistence farmers may be relatively unexposed whereas those in the cash economy travel more, and may be more likely to come forward for diagnosis. In this setting "better houses" may be less well ventilated and residents may spend more time indoors.
    PLoS ONE 10/2013; 8(10):e77740. DOI:10.1371/journal.pone.0077740

Publication Stats

6k Citations
1,547.28 Total Impact Points

Institutions

  • 1993–2015
    • London School of Hygiene and Tropical Medicine
      • • Faculty of Epidemiology and Population Health
      • • Department of Infectious Disease Epidemiology
      • • Department of Non-communicable Disease Epidemiology
      Londinium, England, United Kingdom
  • 2012
    • University College London
      • Department of Infection and Population Health
      Londinium, England, United Kingdom
  • 2011
    • Imperial College London
      Londinium, England, United Kingdom
  • 2010
    • National University of Ireland, Galway
      • Department of Zoology
      Galway, C, Ireland
  • 2007
    • Medical Research Council / Uganda Virus Research Institute
      Entebbe, Central Region, Uganda
    • National Institute for Occupational Health
      Johannesburg, Gauteng, South Africa
    • Harvard Medical School
      Boston, Massachusetts, United States
    • Erasmus Universiteit Rotterdam
      Rotterdam, South Holland, Netherlands
  • 2004–2006
    • National University of Ireland, Maynooth
      • Department of Biology
      Maynooth, L, Ireland
    • National Institute for Public Health and the Environment (RIVM)
      • Laboratory for Infectious Diseases and Perinatal Screening
      Utrecht, Provincie Utrecht, Netherlands
  • 2001–2005
    • University of the Witwatersrand
      • Division of Urology
      Johannesburg, Gauteng, South Africa