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INTRODUCTION: The lack of approved specific therapeutic agents to treat coronavirus disease (COVID-19) associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has led to the rapid implementation of convalescent plasma therapy (CPT) trials in many countries, including the United Kingdom. Effective CPT is likely to require high titres of neutralising antibody (nAb) in convalescent donations. Understanding the relationship between functional neutralising antibodies and antibody levels to specific SARS-CoV-2 proteins in scalable assays will be crucial for the success of a large-scale collection. We assessed whether neutralising antibody titres correlated with reactivity in a range of enzyme-linked immunosorbent assays (ELISA) targeting the spike (S) protein, the main target for human immune response. METHODS: Blood samples were collected from 52 individuals with a previous laboratory-confirmed SARS-CoV-2 infection. These were assayed for SARS-CoV-2 nAbs by microneutralisation and pseudo-type assays and for antibodies by four different ELISAs. Receiver operating characteristic (ROC) analysis was used to further identify sensitivity and specificity of selected assays to identify samples containing high nAb levels. RESULTS: All samples contained SARS-CoV-2 antibodies, whereas neutralising antibody titres of greater than 1:20 were detected in 43 samples (83% of those tested) and >1:100 in 22 samples (42%). The best correlations were observed with EUROimmun immunoglobulin G (IgG) reactivity (Spearman Rho correlation coefficient 0.88; p < 0.001). Based on ROC analysis, EUROimmun would detect 60% of samples with titres of >1:100 with 100% specificity using a reactivity index of 9.1 (13/22). DISCUSSION: Robust associations between nAb titres and reactivity in several ELISA-based antibody tests demonstrate their possible utility for scaled-up production of convalescent plasma containing potentially therapeutic levels of anti-SARS-CoV-2 nAbs.
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Anticorpos Neutralizantes/sangue , COVID-19/terapia , SARS-CoV-2/imunologia , Anticorpos Antivirais/sangue , Doadores de Sangue , COVID-19/diagnóstico , Teste para COVID-19 , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imunização Passiva/métodos , Masculino , Curva ROC , Sensibilidade e Especificidade , Soroterapia para COVID-19RESUMO
INTRODUCTION: Hepatitis C virus (HCV) is the second largest contributor to liver disease in the UK, with injecting drug use as the main risk factor among the estimated 200 000 people currently infected. Despite effective prevention interventions, chronic HCV prevalence remains around 40% among people who inject drugs (PWID). New direct-acting antiviral (DAA) HCV therapies combine high cure rates (>90%) and short treatment duration (8 to 12 weeks). Theoretical mathematical modelling evidence suggests HCV treatment scale-up can prevent transmission and substantially reduce HCV prevalence/incidence among PWID. Our primary aim is to generate empirical evidence on the effectiveness of HCV 'Treatment as Prevention' (TasP) in PWID. METHODS AND ANALYSIS: We plan to establish a natural experiment with Tayside, Scotland, as a single intervention site where HCV care pathways are being expanded (including specialist drug treatment clinics, needle and syringe programmes (NSPs), pharmacies and prison) and HCV treatment for PWID is being rapidly scaled-up. Other sites in Scotland and England will act as potential controls. Over 2 years from 2017/2018, at least 500 PWID will be treated in Tayside, which simulation studies project will reduce chronic HCV prevalence among PWID by 62% (from 26% to 10%) and HCV incidence will fall by approximately 2/3 (from 4.2 per 100 person-years (p100py) to 1.4 p100py). Treatment response and re-infection rates will be monitored. We will conduct focus groups and interviews with service providers and patients that accept and decline treatment to identify barriers and facilitators in implementing TasP. We will conduct longitudinal interviews with up to 40 PWID to assess whether successful HCV treatment alters their perspectives on and engagement with drug treatment and recovery. Trained peer researchers will be involved in data collection and dissemination. The primary outcome - chronic HCV prevalence in PWID - is measured using information from the Needle Exchange Surveillance Initiative survey in Scotland and the Unlinked Anonymous Monitoring Programme in England, conducted at least four times before and three times during and after the intervention. We will adapt Bayesian synthetic control methods (specifically the Causal Impact Method) to generate the cumulative impact of the intervention on chronic HCV prevalence and incidence. We will use a dynamic HCV transmission and economic model to evaluate the cost-effectiveness of the HCV TasP intervention, and to estimate the contribution of the scale-up in HCV treatment to observe changes in HCV prevalence. Through the qualitative data we will systematically explore key mechanisms of TasP real world implementation from provider and patient perspectives to develop a manual for scaling up HCV treatment in other settings. We will compare qualitative accounts of drug treatment and recovery with a 'virtual cohort' of PWID linking information on HCV treatment with Scottish Drug treatment databases to test whether DAA treatment improves drug treatment outcomes. ETHICS AND DISSEMINATION: Extending HCV community care pathways is covered by ethics (ERADICATE C, ISRCTN27564683, Super DOT C Trial clinicaltrials.gov: NCT02706223). Ethical approval for extra data collection from patients including health utilities and qualitative interviews has been granted (REC ref: 18/ES/0128) and ISCRCTN registration has been completed (ISRCTN72038467). Our findings will have direct National Health Service and patient relevance; informing prioritisation given to early HCV treatment for PWID. We will present findings to practitioners and policymakers, and support design of an evaluation of HCV TasP in England.
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Antivirais/administração & dosagem , Controle de Doenças Transmissíveis , Redução do Dano/efeitos dos fármacos , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica , Abuso de Substâncias por Via Intravenosa , Controle de Doenças Transmissíveis/economia , Controle de Doenças Transmissíveis/métodos , Análise Custo-Benefício , Transmissão de Doença Infecciosa/prevenção & controle , Monitoramento de Medicamentos/métodos , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/etiologia , Hepatite C Crônica/prevenção & controle , Humanos , Incidência , Ensaios Clínicos Controlados Aleatórios como Assunto , Escócia/epidemiologia , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologiaRESUMO
BACKGROUND: Persistent hepatitis E virus genotype 3 (HEV G3) infections affect solid organ transplant (SOT) recipients and hematopoietic stem cell transplant (HSCT) recipients, but the burden in these cohorts in the United Kingdom is unknown. We established an audit to determine the point prevalence of HEV viremia in SOT and HSCT patients in the United Kingdom and compare different testing approaches to inform screening strategies. METHODS: Between January 5, 2016, and September 21, 2016, 3044 patients undergoing therapeutic drug monitoring at a single transplant center were screened for HEV ribonucleic acid (RNA) in minipools. A total of 2822 patients who could be characterized included 2419 SOT patients, 144 HSCT patients and 259 patients with no available transplant history. HEV RNA-positive samples were characterized by serology and genomic phylogeny. HEV antigen (HEV-Ag) testing was performed on RNA-positive samples, 420 RNA-negative samples and 176 RNA-negative blood donor samples. RESULTS: Nineteen of 2822 patients were viremic with G3 HEV giving a prevalence of 0.67%. The median alanine aminotransferase was significantly higher in the HEV viremic patients (P < 0.0001); however, 2 viremic patients had an alanine aminotransferase value within the normal range at the time of screening. The HEV-Ag assay identified 18/19 viremic patients and all those patients with proven viremia longer than 4 weeks. CONCLUSIONS: Transplant recipients in the United Kingdom are at a low but significant risk of HEV infection. HEV-Ag detection could be an alternative to RNA detection where the goal is to identify established persistent HEV infection, particularly where expertise, facilities, or cost prohibit RNA testing.
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Vírus da Hepatite E/isolamento & purificação , Hepatite E/diagnóstico , Programas de Rastreamento/estatística & dados numéricos , Transplante de Órgãos/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Viremia/epidemiologia , Adulto , Idoso , Efeitos Psicossociais da Doença , Feminino , Antígenos de Hepatite/isolamento & purificação , Hepatite E/epidemiologia , Hepatite E/virologia , Vírus da Hepatite E/genética , Vírus da Hepatite E/imunologia , Humanos , Masculino , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/virologia , Prevalência , Estudos Prospectivos , RNA Viral/isolamento & purificação , Transplantados/estatística & dados numéricos , Reino Unido/epidemiologia , Viremia/virologia , Adulto JovemRESUMO
BACKGROUND: Hepatitis E virus (HEV) is endemic in EU/EEA countries, but the understanding of the burden of the infection in humans is inconsistent as the disease is not under EU surveillance but subject to national policies. STUDY: Countries were asked to nominate experts and to complete a standardised questionnaire about the epidemiological situation and surveillance of HEV in their respective EU/EEA country. This study reviewed surveillance systems for human cases of HEV in EU/EEA countries and nominated experts assessed the epidemiology in particular examining the recent increase in the number of autochthonous cases. RESULTS: Surveillance systems and case definitions across EU/EEA countries were shown to be highly variable and testing algorithms were unreliable. Large increases of autochthonous cases were reported from Western EU/EEA countries with lower case numbers seen in Northern and Southern European countries. Lack of clinical awareness and variability in testing strategies might account for the observed differences in hepatitis E incidence across EU/EEA countries. Infections were predominantly caused by HEV genotype 3, the most prevalent virus type in the animal reservoirs. CONCLUSION: Discussions from the expert group supported joint working across countries to better monitor the epidemiology and possible changes in risk of virus acquisition at a European level. There was agreement to share surveillance strategies and algorithms but also importantly the collation of HEV data from human and animal populations. These data collected at a European level would serve the 'One Health' approach to better informing on human exposure to HEV.
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Doenças Endêmicas , Hepatite/epidemiologia , Efeitos Psicossociais da Doença , Europa (Continente)/epidemiologia , HumanosRESUMO
OBJECTIVES: To re-assess the prevalence and patient characteristics of hepatitis D virus (HDV) infection among hepatitis B patients in inner city London. METHODS: All hepatitis B patients attending clinics over a 52 months period were tested for HDV antibody. All reactive samples were also tested for anti-HDV IgM and RNA. The characteristics of HDV seronegative patients first seen in the calendar year 2008 were compared with all HDV seropositive patients in the cohort. RESULTS: Of 1048 hepatitis B patients, 11 had equivocal anti-HDV serology (1%) and 22 were HDV seropositive (2.1%, 95%CI 1.39-3.16%); 12 were anti-HDV IgM positive and 15 HDV RNA positive. No patient with equivocal anti-HDV serology had detectable HDV RNA. Five HDV seropositive patients were intravenous drug users (22.7%); 17/22 were from abroad with 11/22 (50%) from sub-Saharan Africa. HDV seropositive patients had poorer laboratory parameters and were more likely to have evidence of cirrhosis. Triple infected (HIV/HBV/HDV) patients were also more likely to have cirrhosis than HIV/HBV dually infected patients. CONCLUSIONS: The prevalence of HDV in hepatitis B patients in inner city London was about 2%. The role of migration from endemic countries should be recognised.