Publications by authors named "Coussens A"

Background: World Health Organization (WHO) tuberculosis (TB) screening guidelines recommend computer-aided detection (CAD) software for chest radiograph (CXR) interpretation. However, studies evaluating their diagnostic and prognostic accuracy are limited.

Methods: We conducted a prospective cohort study of household contacts of rifampicin-resistant TB in South Africa.

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Coaches are recognized as key support providers, although there is limited understanding of how coach support relates to athletes' self-confidence and psychological wellbeing. This study examined relationships among perceived coach support, received coach support, coach-athlete relationship, self-confidence, and psychological wellbeing. A further aim was to identify mechanisms through which coach-athlete relationship influences self-confidence and psychological wellbeing.

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Introduction: Indoor cycling at home has grown rapidly in recent years facilitated by advances in technology and gamification. However, there is limited data on individual's training practices when cycling indoors.

Methods: Using a single-time point, cross-sectional questionnaire, we gathered information on equipment, environmental considerations, training practices and nutrition during indoor cycling.

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Post-tuberculosis (post-TB) lung disease is increasingly recognized as a major contributor to the global burden of chronic lung disease, with recent estimates indicating that over half of TB survivors have impaired lung function after successful completion of TB treatment. However, the pathologic mechanisms that contribute to post-TB lung disease are not well understood, thus limiting the development of therapeutic interventions to improve long-term outcomes after TB. This report summarizes the work of the Pathogenesis and Risk Factors Committee for the Second International Post-Tuberculosis Symposium, which took place in Stellenbosch, South Africa, in April 2023.

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BACKGROUNDIn recent years, there has been increasing recognition of the public health significance of the spectrum of TB disease presentation, and the existing classification systems of asymptomatic infection and symptomatic TB have been limited in terms of explanatory power. Accordingly, in 2022-2023, a new International Consensus framework for Early TB (ICE-TB) was developed, categorising the spectrum of TB infection and disease into five states based on the presence or absence of macroscopic pathology, host infectiousness, and symptoms and signs.METHODSWe used the ICE-TB framework to re-analyse existing notification data for 2022 within a low-incidence setting to explore the potential utility and future challenges for its public health application.

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Tuberculosis (TB) is caused by (). Following infection, immune responses to antigens can be measured using the tuberculin skin test or an interferon-γ release assay. The gain of immunoreactivity, a change from a negative to a positive tuberculin skin test or interferon-γ release assay result, is called conversion and has long been used as a measure of exposure.

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  • The study focuses on childhood TB infection prevalence, incidence, and risk factors in Cape Town, South Africa, highlighting the importance of understanding TB transmission.
  • Using a large sample of primary school children from high TB burden areas, researchers measured TB infection at baseline and tracked changes over three years through the QFT-Plus test.
  • Findings indicate a high prevalence of TB infection (22.6%) associated with factors like age and household exposure to TB, emphasizing the need for effective contact tracing and early treatment to reduce transmission in the community.
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  • - Vaccine development for SARS-CoV-2 in 2020 was essential for reducing COVID-19 severity, with the U.K. primarily using Pfizer's BNT162b2 and Oxford/AstraZeneca's ChAdOx1-nCoV-19 vaccines during the initial roll-out.
  • - A study analyzed the effects of age, sex, BMI, and pre-vaccination antibody levels on immune responses in participants, revealing that younger age and existing antibodies led to stronger antibody responses.
  • - Findings showed that the Pfizer vaccine produced higher antibody levels compared to the AstraZeneca vaccine, but age and BMI negatively impacted both cellular and humoral responses to vaccination.
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  • - The study aimed to see if weekly vitamin D supplementation affects growth, body composition, pubertal development, or lung function in South African schoolchildren aged 6-11 years, through a rigorous 3-year double-blind trial.
  • - 1682 children participated, with one group receiving 10,000 IU of vitamin D weekly and a control group receiving a placebo, while growth and health measures were closely monitored.
  • - Results showed that while vitamin D levels increased significantly in the supplemented group, there were no meaningful changes in growth, body composition, or lung function compared to the placebo group.
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The current active-latent paradigm of tuberculosis largely neglects the documented spectrum of disease. Inconsistency with regard to definitions, terminology, and diagnostic criteria for different tuberculosis states has limited the progress in research and product development that are needed to achieve tuberculosis elimination. We aimed to develop a new framework of classification for tuberculosis that accommodates key disease states but is sufficiently simple to support pragmatic research and implementation.

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  • There is a lack of randomized controlled trials (RCTs) investigating the impact of vitamin D on bone mineral content (BMC) and fracture risk in Black African children, leading to this sub-study among 450 Cape Town schoolchildren aged 6-11.
  • The study found that after a 3-year vitamin D supplementation of 10,000 IU weekly, participants had higher serum vitamin D levels and lower parathyroid hormone (PTH) levels, but no significant differences in BMC or bone turnover markers between the vitamin D and placebo groups.
  • Fractures were infrequent in both the vitamin D and placebo groups, suggesting that while vitamin D supplementation improved some biochemical markers, it did not significantly affect bone density or
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There is growing recognition that tuberculosis (TB) infection and disease exists as a spectrum of states beyond the current binary classification of latent and active TB. Our aim was to systematically map and synthesize published conceptual frameworks for TB states. We searched MEDLINE, Embase and EMcare for review articles from 1946 to September 2023.

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Background: Diagnostic specimens for spinal tuberculosis (STB) are mostly collected via open surgery. Percutaneous computed tomography (CT)-guided biopsies are used in times of limited surgical availability. However, poor diagnostic accuracy of () culture has been reported with this method, due to limited sample volume and the paucibacillary nature of STB.

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Macrophages provide a first line of defense against invading pathogens, including the leading cause of bacterial mortality, Mycobacterium tuberculosis (Mtb). A challenge for quantitative characterization of host-pathogen processes in differentially polarized primary human monocyte-derived macrophages (MDMs) is their heterogeneous morphology. Here, we describe the use of microfabricated patterns that constrain the size and shape of cells, mimicking the physiological spatial confinement cells experience in tissues, to quantitatively characterize interactions during and after phagocytosis at the single-cell level at high resolution.

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SARS-CoV-2 and () are major infectious causes of death, with meta-analyses and population-based studies finding increased mortality in co-infected patients simultaneously diagnosed with COVID-19 and tuberculosis (TB). There is a need to understand the immune interaction between SARS-CoV-2 and which impacts poor outcomes for those co-infected. We performed a PubMed and preprint search using keywords [SARS-CoV-2] AND [tuberculosis] AND [Immune response], including publications after January 2020, excluding reviews or opinions.

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Persons living with HIV (PLWH) have an increased risk for tuberculosis (TB). After prolonged and repeated exposure, some PLWH never develop TB and show no evidence of immune sensitization to Mycobacterium tuberculosis (Mtb) as defined by persistently negative tuberculin skin tests (TST) and interferon gamma release assays (IGRA). This group has been identified and defined as HIV+ persistently TB, tuberculin and IGRA negative (HITTIN).

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The diversity of COVID-19 disease in otherwise healthy people, from seemingly asymptomatic infection to severe life-threatening disease, is not clearly understood. We passaged a naturally occurring near-ancestral SARS-CoV-2 variant, capable of infecting wild-type mice, and identified viral genomic mutations coinciding with the acquisition of severe disease in young adult mice and lethality in aged animals. Transcriptomic analysis of lung tissues from mice with severe disease elucidated a host antiviral response dominated mainly by interferon and IL-6 pathway activation in young mice, while in aged animals, a fatal outcome was dominated by TNF and TGF-β signaling.

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Background: The evolution of tuberculosis (TB) disease during the clinical latency period remains incompletely understood.

Methods: 250 HIV-uninfected, adult household contacts of rifampicin-resistant TB with a negative symptom screen underwent baseline F-Fluorodeoxyglucose positron emission and computed tomography (PET/CT), repeated in 112 after 5-15 months. Following South African and WHO guidelines, participants did not receive preventive therapy.

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Objectives: To determine whether weekly oral supplementation with 10,000 IU vitamin D for 3 years reduces the risk of sensitization to M. tuberculosis in South African schoolchildren aged 6-11 years with negative QuantiFERON-tuberculosis (TB) Gold Plus (QFT-Plus) assay results at baseline.

Methods: We conducted a phase 3 randomized placebo-controlled trial in 1682 children attending 23 primary schools in Cape Town.

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When profiling blood samples by RNA-sequencing (RNA-seq), RNA from haemoglobin (Hgb) can account for up to 70% of the transcriptome. Due to considerations of sequencing depth and power to detect biological variation, Hgb RNA is typically depleted prior to sequencing by hybridisation-based methods; an alternative approach is to deplete reads arising from Hgb RNA bioinformatically. In the present study, we compared the impact of these two approaches on the outcome of differential gene expression analysis performed using RNA-seq data from 58 human tuberculosis (TB) patient or contact whole blood samples-29 globin kit-depleted and 29 matched non-depleted-a subset of which were taken at TB diagnosis and at six months post-TB treatment from the same patient.

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Few studies from Africa have described the clinical impact of co-infections on SARS-CoV-2 infection. Here, we investigate the presentation and outcome of SARS-CoV-2 infection in an African setting of high HIV-1 and tuberculosis prevalence by an observational case cohort of SARS-CoV-2 patients. A comparator group of non SARS-CoV-2 participants is included.

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Vitamin D deficiency has been reported to associate with the impaired development of antigen-specific responses following vaccination. We aimed to determine whether vitamin D supplements might boost the immunogenicity and efficacy of SARS-CoV-2 vaccination by conducting three sub-studies nested within the CORONAVIT randomised controlled trial, which investigated the effects of offering vitamin D supplements at a dose of 800 IU/day or 3200 IU/day vs. no offer on risk of acute respiratory infections in UK adults with circulating 25-hydroxyvitamin D concentrations <75 nmol/L.

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Current and previous tuberculosis (TB) increase the risk of COVID-19 mortality and severe disease. To identify mechanisms of immunopathogenic interaction between COVID-19 and TB, we performed a systematic review and patient-level meta-analysis of COVID-19 transcriptomic signatures, spanning disease severity, from whole blood, PBMCs, and BALF. 35 eligible signatures were profiled on 1181 RNA-seq samples from 853 individuals across the spectrum of TB infection.

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We currently have a binomial approach to managing tuberculosis. Those with active disease, ideally confirmed microbiologically, are treated with a standard 6-month, multi-drug regimen and those with latent infection and no evidence of disease with shorter, one or two drug regimens. Clinicians frequently encounter patients that fall between these two management pathways with some but not all features of disease and this will occur more often with the increasing emphasis on chest X-ray-based systematic screening.

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