London School of Hygiene & Tropical Medicine

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    Identification of Burkholderia cepacia strains that express a Burkholderia pseudomallei-like capsular polysaccharide.

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    Burkholderia pseudomallei and Burkholderia cepacia are Gram-negative, soil-dwelling bacteria that are found in a wide variety of environmental niches. While B. pseudomallei is the causative agent of melioidosis in humans and animals, members of the B. cepacia complex typically only cause disease in immunocompromised hosts. In this study, we report the identification of B. cepacia strains isolated from either patients or soil in Laos and Thailand that express a B. pseudomallei-like 6-deoxyheptan capsular polysaccharide (CPS). These B. cepacia strains were initially identified based on their positive reactivity in a latex agglutination assay that uses the CPS-specific monoclonal antibody (mAb) 4B11. Mass spectrometry and recA sequencing confirmed the identity of these isolates as B. cepacia (formerly genomovar I). Total carbohydrates extracted from B. cepacia cell pellets reacted with B. pseudomallei CPS-specific mAbs MCA147, 3C5, and 4C4, but did not react with the B. pseudomallei lipopolysaccharide-specific mAb Pp-PS-W. Whole genome sequencing of the B. cepacia isolates revealed the presence of genes demonstrating significant homology to those comprising the B. pseudomallei CPS biosynthetic gene cluster. Collectively, our results provide compelling evidence that B. cepacia strains expressing the same CPS as B. pseudomallei co-exist in the environment alongside B. pseudomallei. Since CPS is a target that is often used for presumptive identification of B. pseudomallei, it is possible that the occurrence of these unique B. cepacia strains may complicate the diagnosis of melioidosis.IMPORTANCEBurkholderia pseudomallei, the etiologic agent of melioidosis, is an important cause of morbidity and mortality in tropical and subtropical regions worldwide. The 6-deoxyheptan capsular polysaccharide (CPS) expressed by this bacterial pathogen is a promising target antigen that is useful for rapidly diagnosing melioidosis. Using assays incorporating CPS-specific monoclonal antibodies, we identified both clinical and environmental isolates of Burkholderia cepacia that express the same CPS antigen as B. pseudomallei. Because of this, it is important that staff working in melioidosis-endemic areas are aware that these strains co-exist in the same niches as B. pseudomallei and do not solely rely on CPS-based assays such as latex-agglutination, AMD Plus Rapid Tests, or immunofluorescence tests for the definitive identification of B. pseudomallei isolates

    Association between tuberculosis and pregnancy outcomes: a retrospective cohort study of women in Cape Town, South Africa.

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    BACKGROUND: Tuberculosis (TB) remains a leading cause of mortality among women of childbearing age and a significant contributor to maternal mortality. Pregnant women with TB are at high risk of adverse pregnancy outcomes. This study aimed to determine risk factors for an adverse pregnancy outcome among pregnant women diagnosed with TB. METHODS: Using TB programmatic data, this retrospective cohort analysis included all women who were routinely diagnosed with TB in the public sector between October 2018 and March 2020 in two health subdistricts of Cape Town, and who were documented to be pregnant during their TB episode. Adverse pregnancy outcome was defined as either a live birth of an infant weighing <2500 g and/or with a gestation period <37 weeks or as stillbirth, miscarriage, termination of pregnancy, maternal or early neonatal death. Demographics, TB and pregnancy characteristics were described by HIV status. Logistic regression was used to determine risk factors for adverse pregnancy outcome. RESULTS: Of 248 pregnant women, half (52%) were living with HIV; all were on antiretroviral therapy at the time of their TB diagnosis. Pregnancy outcomes were documented in 215 (87%) women, of whom 74 (34%) had an adverse pregnancy outcome. Being older (35-44 years vs 25-34 years (adjusted OR (aOR): 3.99; 95% CI: 1.37 to 11.57), living with HIV (aOR: 2.72; 95% CI: 0.99 to 4.63), having an unfavourable TB outcome (aOR: 2.29; 95% CI: 1.03 to 5.08) and having presented to antenatal services ≤1 month prior to delivery (aOR: 10.57; 95% CI: 4.01 to 27.89) were associated with higher odds of an adverse pregnancy outcome. CONCLUSIONS: Pregnancy outcomes among women with TB were poor, irrespective of HIV status. Pregnant women with TB are a complex population who need additional support prior to, during and after TB treatment to improve TB treatment and pregnancy outcomes. Pregnancy status should be considered for inclusion in TB registries

    Addressing Ancestry and Sex Bias in Pharmacogenomics.

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    The association of an individual's genetic makeup with their response to drugs is referred to as pharmacogenomics. By understanding the relationship between genetic variants and drug efficacy or toxicity, we are able to optimize pharmacological therapy according to an individual's genotype. Pharmacogenomics research has historically suffered from bias and underrepresentation of people from certain ancestry groups and of the female sex. These biases can arise from factors such as drugs and indications studied, selection of study participants, and methods used to collect and analyze data. To examine the representation of biogeographical populations in pharmacogenomic data sets, we describe individuals involved in gene-drug response studies from PharmGKB, a leading repository of drug-gene annotations, and showcaseCYP2D6, a gene that metabolizes approximately 25% of all prescribed drugs. We also show how the historical underrepresentation of females in clinical trials has led to significantly more adverse drug reactions in females than in males

    Equity impact of HPV vaccination on lifetime projections of cervical cancer burden among cohorts in 84 countries by global, regional, and income levels, 2010-22: a modelling study.

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    BACKGROUND: While human papillomavirus (HPV) vaccines have been available since 2006, the coverage has varied among countries. Our aim is to analyse the equity impact of HPV vaccination on the lifetime projections of cervical cancer burden among vaccinated cohorts of 2010-22 in 84 countries. METHODS: We used WHO and UNICEF estimates of national immunisation coverage for HPV vaccination in 84 countries during 2010-22. We used PRIME (Papillomavirus Rapid Interface for Modelling and Economics) to estimate the lifetime health impact of HPV vaccination on cervical cancer burden in terms of deaths, cases, and disability-adjusted life years (DALYs) averted by vaccination in their respective countries. We generated concentration indices and curves to assess the equity impact of HPV vaccination across 84 countries. FINDINGS: The health impact of HPV vaccination varied across the 84 countries and ranged from Switzerland to Tanzania at 2 to 34 deaths, 4 to 47 cases, and 40 to 735 DALYs averted per 1000 vaccinated adolescent girls over the lifetime of the vaccinated cohorts of 2010-22. The concentration index for the distribution of average coverage during 2010-22 among the 84 countries ranked by vaccine impact was 0.33 (95% CI: 0.27-0.40) and highlights the wide inequities in HPV vaccination coverage. INTERPRETATION: Our findings suggested that countries with a relatively higher cervical cancer burden and thereby a relatively higher need for HPV vaccination had relatively lower coverage during 2010-22. Further, there were significant inequities in HPV vaccination coverage within the Americas, Europe, and Western Pacific regions, and in high- and low-income countries with a pro-advantaged and regressive distribution favouring countries with lower vaccine impact. FUNDING: Gavi, the Vaccine Alliance; Bill & Melinda Gates Foundation

    Israeli necropolitics and the pursuit of health justice in Palestine.

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    We abhor the continuation and acceleration of the Israeli state's systemic violence against the Palestinian people. We reassert that resolution of the settler colonial root causes of violence in Palestine is central to the pursuit of justice and peace. The moral foundations of global health and medical practice require us to prioritise and foreground oppressed realities, and to practise epistemic resistance. Framing Palestinian violence on October 7 as provocation and Israeli violence as response is ahistoric and indicates indifference to the everyday violence experienced by Palestinians. The Israeli state practises both fast violence against Palestinians, while simultaneously creating the conditions for their ‘slow death’. The systematic targeting and destruction of the health system and healthcare workers in Gaza has been central to Israel's military strategy, while many Israeli officials have expressed clear genocidal intent. The occupation of Palestine demonstrates the horrors of Israeli necropolitics, which leads to the creation of 'death-worlds' in which people survive and resist in perpetual proximity to death

    Treat All versus targeted strategies to select HBV-infected people for antiviral therapy in The Gambia, west Africa: a cost-effectiveness analysis.

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    BACKGROUND: Global elimination of hepatitis B virus (HBV) requires expanded uptake of antiviral therapy, potentially by simplifying testing algorithms, especially in resource-limited countries. We evaluated the effectiveness, cost-effectiveness, and budget impact of three strategies that determine eligibility for anti-HBV treatment, as compared with the WHO 2015 treatment eligibility criteria, in The Gambia. METHODS: We developed a microsimulation model of natural history using data from the Prevention of Liver Fibrosis and Cancer in Africa programme (known as PROLIFICA) in The Gambia, for an HBV-infected cohort of individuals aged 20 years. The algorithms included in the model were a conventional strategy using the European Association for the Study of the Liver (EASL) 2017 criteria, a simplified algorithm using hepatitis B e antigen and alanine aminotransferase (the Treatment Eligibility in Africa for the Hepatitis B Virus [TREAT-B] score), a Treat All approach for all HBV-infected individuals, and the WHO 2015 criteria. Outcomes to measure effectiveness were disability-adjusted life years (DALYs) and years of life saved (YLS), which were used to calculate incremental cost-effectiveness ratios (ICERs) with the WHO 2015 criteria as the base-case scenario. Costs were assessed from a modified social perspective. A budget impact analysis was also done. We tested the robustness of results with a range of sensitiviy analyses including probabilistic sensitivity analysis. FINDINGS: Compared with the WHO criteria, TREAT-B resulted in 4877 DALYs averted and Treat All resulted in 9352 DALYs averted, whereas the EASL criteria led to an excess of 795 DALYs. TREAT-B was cost-saving, whereas the ICER for Treat All (US2149perDALYaverted)washigherthanthecosteffectivenessthresholdforTheGambia(05timesthecountrysgrossdomesticproductpercapita:2149 per DALY averted) was higher than the cost-effectiveness threshold for The Gambia (0·5 times the country's gross domestic product per capita: 352). These patterns did not change when YLS was the outcome. In a modelled cohort of 5000 adults (aged 20 years) with chronic HBV infection from The Gambia, the 5-year budget impact was 114millionforTreatAll,1·14 million for Treat All, 0·66 million for TREAT-B, 103millionfortheWHOcriteria,and1·03 million for the WHO criteria, and 1·16 million for the EASL criteria. Probabilistic sensitivity analysis indicated that among the Treat All, EASL, and TREAT-B algorithms, Treat All would become the most preferred strategy only with a willingness-to-pay threshold exceeding approximately 72000perDALYavertedor72 000 per DALY averted or 110 000 per YLS. INTERPRETATION: Although the Treat All strategy might be the most effective, it is unlikely to be cost-effective in The Gambia. A simplified strategy such as TREAT-B might be a cost-saving alternative. FUNDING: UK Research and Innovation (Medical Research Council). TRANSLATION: For the French translation of the abstract see Supplementary Materials section

    The Enterics for Global Health (EFGH) Shigella Surveillance Study in The Gambia.

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    BACKGROUND: The Gambia, located in West Africa, is one of 7 country sites conducting the Enterics for Global Health (EFGH) Shigella Surveillance Study to establish incidence and consequence of Shigella-associated medically attended diarrhea among children 6-35 months old. METHODS: Here we describe the study site and research experience, sociodemographic characteristics of the study catchment area, facilities of recruitment for diarrhea case surveillance, and known care-seeking behavior for diarrheal illness. We also describe The Gambia's healthcare system and financing, current vaccine schedule and Shigella vaccine adaptation, local diarrhea management guidelines and challenges, and antibiotic resistance patterns in the region. CONCLUSIONS: The EFGH study in The Gambia will contribute to the multisite network of Shigella surveillance study and prepare the site for future vaccine trials. In addition, the data produced will inform policy makers about prevention strategies and upcoming Shigella vaccine studies among children in this setting

    Tobacco smoking clusters in households affected by tuberculosis in an individual participant data meta-analysis of national tuberculosis prevalence surveys: Time for household-wide interventions?

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    Tuberculosis (TB) and non-communicable diseases (NCD) share predisposing risk factors. TB-associated NCD might cluster within households affected with TB requiring shared prevention and care strategies. We conducted an individual participant data meta-analysis of national TB prevalence surveys to determine whether NCD cluster in members of households with TB. We identified eligible surveys that reported at least one NCD or NCD risk factor through the archive maintained by the World Health Organization and searching in Medline and Embase from 1 January 2000 to 10 August 2021, which was updated on 23 March 2023. We compared the prevalence of NCD and their risk factors between people who do not have TB living in households with at least one person with TB (members of households with TB), and members of households without TB. We included 16 surveys (n = 740,815) from Asia and Africa. In a multivariable model adjusted for age and gender, the odds of smoking was higher among members of households with TB (adjusted odds ratio (aOR) 1.23; 95% CI: 1.11-1.38), compared with members of households without TB. The analysis did not find a significant difference in the prevalence of alcohol drinking, diabetes, hypertension, or BMI between members of households with and without TB. Studies evaluating household-wide interventions for smoking to reduce its dual impact on TB and NCD may be warranted. Systematically screening for NCD using objective diagnostic methods is needed to understand the actual burden of NCD and inform comprehensive interventions

    The Royal College of Ophthalmologists' National Ophthalmology Database Study of Cataract Surgery: Report 13, monitoring post-cataract surgery endophthalmitis rates-the rule of X.

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    BACKGROUND: Cataract surgical safety has improved over recent decades, with endophthalmitis rates before 2006 typically 0.13-0.15% compared with the most recent UK national estimate of 0.02%. There remains, however, substantial variation in reported rates from different centres. Due to the low event rate, this disparity may not be noticed and opportunities to improve therefore be missed. We propose a method of monitoring post-cataract endophthalmitis rates that would help centres with higher rates identify this. METHODS: A statistical tool, available to download or use online, permits comparison of local endophthalmitis rate with the estimated UK rate of 0.02%. Centres are encouraged to maintain a register of endophthalmitis cases, and when the number reaches a threshold (X cases), either in a certain time period or in a fixed number of procedures, then the centre can consider itself as an outlier and trigger local investigations to improve infection control. RESULTS: Example outputs are offered, such as for a unit doing 5000 cataracts annually, a value of X is suggested such that the third case of endophthalmitis (X = 3) in a 12-month period would give 85% confidence, the fourth case 90% confidence and the fifth case 95% confidence that the true endophthalmitis rate for that unit was higher than the national average. CONCLUSIONS: This statistical tool provides a basis for units to set a threshold number of cases of endophthalmitis within a given period that would trigger local processes, thus helping inform local monitoring processes for this rare but potentially catastrophic complication of cataract surgery

    Ozone-related acute excess mortality projected to increase in the absence of climate and air quality controls consistent with the Paris Agreement.

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    Short-term exposure to ground-level ozone in cities is associated with increased mortality and is expected to worsen with climate and emission changes. However, no study has yet comprehensively assessed future ozone-related acute mortality across diverse geographic areas, various climate scenarios, and using CMIP6 multi-model ensembles, limiting our knowledge on future changes in global ozone-related acute mortality and our ability to design targeted health policies. Here, we combine CMIP6 simulations and epidemiological data from 406 cities in 20 countries or regions. We find that ozone-related deaths in 406 cities will increase by 45 to 6,200 deaths/year between 2010 and 2014 and between 2050 and 2054, with attributable fractions increasing in all climate scenarios (from 0.17% to 0.22% total deaths), except the single scenario consistent with the Paris Climate Agreement (declines from 0.17% to 0.15% total deaths). These findings stress the need for more stringent air quality regulations, as current standards in many countries are inadequate

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