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1.
N Engl J Med ; 390(9): 806-818, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38416429

RESUMEN

BACKGROUND: Cognitive symptoms after coronavirus disease 2019 (Covid-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are well-recognized. Whether objectively measurable cognitive deficits exist and how long they persist are unclear. METHODS: We invited 800,000 adults in a study in England to complete an online assessment of cognitive function. We estimated a global cognitive score across eight tasks. We hypothesized that participants with persistent symptoms (lasting ≥12 weeks) after infection onset would have objectively measurable global cognitive deficits and that impairments in executive functioning and memory would be observed in such participants, especially in those who reported recent poor memory or difficulty thinking or concentrating ("brain fog"). RESULTS: Of the 141,583 participants who started the online cognitive assessment, 112,964 completed it. In a multiple regression analysis, participants who had recovered from Covid-19 in whom symptoms had resolved in less than 4 weeks or at least 12 weeks had similar small deficits in global cognition as compared with those in the no-Covid-19 group, who had not been infected with SARS-CoV-2 or had unconfirmed infection (-0.23 SD [95% confidence interval {CI}, -0.33 to -0.13] and -0.24 SD [95% CI, -0.36 to -0.12], respectively); larger deficits as compared with the no-Covid-19 group were seen in participants with unresolved persistent symptoms (-0.42 SD; 95% CI, -0.53 to -0.31). Larger deficits were seen in participants who had SARS-CoV-2 infection during periods in which the original virus or the B.1.1.7 variant was predominant than in those infected with later variants (e.g., -0.17 SD for the B.1.1.7 variant vs. the B.1.1.529 variant; 95% CI, -0.20 to -0.13) and in participants who had been hospitalized than in those who had not been hospitalized (e.g., intensive care unit admission, -0.35 SD; 95% CI, -0.49 to -0.20). Results of the analyses were similar to those of propensity-score-matching analyses. In a comparison of the group that had unresolved persistent symptoms with the no-Covid-19 group, memory, reasoning, and executive function tasks were associated with the largest deficits (-0.33 to -0.20 SD); these tasks correlated weakly with recent symptoms, including poor memory and brain fog. No adverse events were reported. CONCLUSIONS: Participants with resolved persistent symptoms after Covid-19 had objectively measured cognitive function similar to that in participants with shorter-duration symptoms, although short-duration Covid-19 was still associated with small cognitive deficits after recovery. Longer-term persistence of cognitive deficits and any clinical implications remain uncertain. (Funded by the National Institute for Health and Care Research and others.).


Asunto(s)
COVID-19 , Disfunción Cognitiva , Trastornos de la Memoria , Adulto , Humanos , Cognición , Disfunción Cognitiva/etiología , COVID-19/complicaciones , Trastornos de la Memoria/etiología , SARS-CoV-2 , Memoria , Inglaterra , Síndrome Post Agudo de COVID-19/etiología
2.
PLoS Biol ; 21(5): e3002118, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37228015

RESUMEN

The relationship between prevalence of infection and severe outcomes such as hospitalisation and death changed over the course of the COVID-19 pandemic. Reliable estimates of the infection fatality ratio (IFR) and infection hospitalisation ratio (IHR) along with the time-delay between infection and hospitalisation/death can inform forecasts of the numbers/timing of severe outcomes and allow healthcare services to better prepare for periods of increased demand. The REal-time Assessment of Community Transmission-1 (REACT-1) study estimated swab positivity for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection in England approximately monthly from May 2020 to March 2022. Here, we analyse the changing relationship between prevalence of swab positivity and the IFR and IHR over this period in England, using publicly available data for the daily number of deaths and hospitalisations, REACT-1 swab positivity data, time-delay models, and Bayesian P-spline models. We analyse data for all age groups together, as well as in 2 subgroups: those aged 65 and over and those aged 64 and under. Additionally, we analysed the relationship between swab positivity and daily case numbers to estimate the case ascertainment rate of England's mass testing programme. During 2020, we estimated the IFR to be 0.67% and the IHR to be 2.6%. By late 2021/early 2022, the IFR and IHR had both decreased to 0.097% and 0.76%, respectively. The average case ascertainment rate over the entire duration of the study was estimated to be 36.1%, but there was some significant variation in continuous estimates of the case ascertainment rate. Continuous estimates of the IFR and IHR of the virus were observed to increase during the periods of Alpha and Delta's emergence. During periods of vaccination rollout, and the emergence of the Omicron variant, the IFR and IHR decreased. During 2020, we estimated a time-lag of 19 days between hospitalisation and swab positivity, and 26 days between deaths and swab positivity. By late 2021/early 2022, these time-lags had decreased to 7 days for hospitalisations and 18 days for deaths. Even though many populations have high levels of immunity to SARS-CoV-2 from vaccination and natural infection, waning of immunity and variant emergence will continue to be an upwards pressure on the IHR and IFR. As investments in community surveillance of SARS-CoV-2 infection are scaled back, alternative methods are required to accurately track the ever-changing relationship between infection, hospitalisation, and death and hence provide vital information for healthcare provision and utilisation.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , SARS-CoV-2 , Teorema de Bayes , Pandemias , Inglaterra/epidemiología , Hospitalización
3.
Hepatology ; 77(5): 1757-1772, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35736236

RESUMEN

Hepatitis C virus (HCV) remains a major global health concern. Directly acting antiviral (DAA) drugs have transformed the treatment of HCV. However, it has become clear that, without an effective HCV vaccine, it will not be possible to meet the World Health Organization targets of HCV viral elimination. Promising new vaccine technologies that generate high magnitude antiviral T and B cell immune responses and significant new funding have recently become available, stimulating the HCV vaccine pipeline. In the absence of an immune competent animal model for HCV, the major block in evaluating new HCV vaccine candidates will be the assessment of vaccine efficacy in humans. The development of a controlled human infection model (CHIM) for HCV could overcome this block, enabling the head-to-head assessment of vaccine candidates. The availability of highly effective DAA means that a CHIM for HCV is possible for the first time. In this review, we highlight the challenges and issues with currently available strategies to assess HCV vaccine efficacy including HCV "at-risk" cohorts and animal models. We describe the development of CHIM in other infections that are increasingly utilized by trialists and explore the ethical and safety concerns specific for an HCV CHIM. Finally, we propose an HCV CHIM study design including the selection of volunteers, the development of an infectious inoculum, the evaluation of host immune and viral parameters, and the definition of study end points for use in an HCV CHIM. Importantly, the study design (including number of volunteers required, cost, duration of study, and risk to volunteers) varies significantly depending on the proposed mechanism of action (sterilizing/rapid viral clearance vs. delayed viral clearance) of the vaccine under evaluation. We conclude that an HCV CHIM is now realistic, that safety and ethical concerns can be addressed with the right study design, and that, without an HCV CHIM, it is difficult to envisage how the development of an HCV vaccine will be possible.


Asunto(s)
Antivirales , Hepatitis C , Animales , Humanos , Antivirales/farmacología , Hepacivirus
4.
Clin Infect Dis ; 76(4): 658-666, 2023 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-35913410

RESUMEN

BACKGROUND: We explore severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody lateral flow immunoassay (LFIA) performance under field conditions compared to laboratory-based electrochemiluminescence immunoassay (ECLIA) and live virus neutralization. METHODS: In July 2021, 3758 participants performed, at home, a self-administered Fortress LFIA on finger-prick blood, reported and submitted a photograph of the result, and provided a self-collected capillary blood sample for assessment of immunoglobulin G (IgG) antibodies using the Roche Elecsys® Anti-SARS-CoV-2 ECLIA. We compared the self-reported LFIA result to the quantitative ECLIA and checked the reading of the LFIA result with an automated image analysis (ALFA). In a subsample of 250 participants, we compared the results to live virus neutralization. RESULTS: Almost all participants (3593/3758, 95.6%) had been vaccinated or reported prior infection. Overall, 2777/3758 (73.9%) were positive on self-reported LFIA, 2811/3457 (81.3%) positive by LFIA when ALFA-reported, and 3622/3758 (96.4%) positive on ECLIA (using the manufacturer reference standard threshold for positivity of 0.8 U mL-1). Live virus neutralization was detected in 169 of 250 randomly selected samples (67.6%); 133/169 were positive with self-reported LFIA (sensitivity 78.7%; 95% confidence interval [CI]: 71.8, 84.6), 142/155 (91.6%; 95% CI: 86.1, 95.5) with ALFA, and 169 (100%; 95% CI: 97.8, 100.0) with ECLIA. There were 81 samples with no detectable virus neutralization; 47/81 were negative with self-reported LFIA (specificity 58.0%; 95% CI: 46.5, 68.9), 34/75 (45.3%; 95% CI: 33.8, 57.3) with ALFA, and 0/81 (0%; 95% CI: 0, 4.5) with ECLIA. CONCLUSIONS: Self-administered LFIA is less sensitive than a quantitative antibody test, but the positivity in LFIA correlates better than the quantitative ECLIA with virus neutralization.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , Autoevaluación , Sensibilidad y Especificidad , Anticuerpos Antivirales , Inmunoensayo/métodos
5.
HIV Med ; 24(4): 471-479, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36172948

RESUMEN

OBJECTIVES: We aimed to describe clinical policies for the management of people with HIV/hepatitis C virus (HCV) coinfection and to audit routine monitoring and assessment of people with HIV/HCV coinfection attending UK HIV care. METHODS: This was a clinic survey and retrospective case-note review. HIV clinics in the UK participated in the audit from May to July 2021 by completing an online questionnaire regarding their clinic's policies for the management of people with HIV/HCV coinfection, and by contributing to a case-note review of people living with HIV with detectable HCV RNA who were under the care of their service. RESULTS: Ninety-five clinics participated in the clinic survey; of these, 15 (15.8%) were regional specialist centres, 19 (20.0%) were HIV services with their own coinfection clinics, 40 (42.1%) were HIV services that referred coinfected individuals to a local hepatology service and 20 (21.1%) were HIV services that referred to a regional specialist centre. Eighty-one clinics provided full caseload estimates; of the approximately 3951 people with a history of HIV/HCV coinfection accessing their clinics, only 4.9% were believed to have detectable HCV RNA, 3.15% of whom were already receiving or approved for direct-acting antiviral (DAA) treatment. In total, 29 (30.5%) of the clinics reported an impact of COVID-19 on coinfection care, including delays or reductions in the frequency of services, monitoring, treatment initiation and appointments, and changes to the way that treatment was dispensed. Case-note reviews were provided for 283 people with detectable HCV RNA from 74 clinics (median age 42 years, 74.6% male, 56.2% HCV genotype 1, 22.3% HCV genotype 3). Overall, 56% had not received treatment for HCV, primarily due to lack of engagement in care (54.7%) and/or being uncontactable (16.4%). CONCLUSIONS: Our findings show that the small number of people with HIV with detectable HCV RNA in the UK should mean that it is possible to achieve HCV micro-elimination. However, more work is needed to improve engagement in care for those who are untreated for HCV.


Asunto(s)
COVID-19 , Coinfección , Infecciones por VIH , Hepatitis C Crónica , Hepatitis C , Humanos , Masculino , Adulto , Femenino , Hepacivirus/genética , Antivirales/uso terapéutico , Estudios Retrospectivos , Coinfección/tratamiento farmacológico , Hepatitis C Crónica/tratamiento farmacológico , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Hepatitis C/complicaciones , Hepatitis C/tratamiento farmacológico
6.
Liver Int ; 43(7): 1427-1439, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37183550

RESUMEN

BACKGROUND AND AIMS: People living with HIV (PLWH) are at high risk for advanced chronic liver disease and related adverse outcomes. We aimed to validate the prognostic value of non-invasive scores based on liver stiffness measurement (LSM) and on markers of portal hypertension (PH), namely platelets and spleen diameter, in PLWH. METHODS: We combined data from eight international cohorts of PLWH with available non-invasive scores, including LSM and the composite biomarkers liver stiffness-spleen size-to-platelet ratio score (LSPS), LSM-to-Platelet ratio (LPR) and PH risk score. Incidence and predictors of all-cause mortality, any liver-related event and classical hepatic decompensation were determined by survival analysis, controlling for competing risks for the latter two. Non-invasive scores were assessed and compared using area under the receiver operating curve (AUROC). RESULTS: We included 1695 PLWH (66.8% coinfected with hepatitis C virus). During a median follow-up of 4.7 (interquartile range 2.8-7.7) years, the incidence rates of any liver-related event, all-cause mortality and hepatic decompensation were 13.7 per 1000 persons-year (PY) (95% confidence interval [CI], 11.4-16.3), 13.8 per 1000 PY (95% CI, 11.6-16.4) and 9.9 per 1000 PY (95% CI, 8.1-12.2), respectively. The AUROC of LSM was similar to that of the composite biomarkers, ranging between 0.83 and 0.86 for any liver-related event, 0.79-0.85 for all-cause mortality and 0.87-0.88 for classical hepatic decompensation. All individual non-invasive scores remained independent predictors of clinical outcomes in multivariable analysis. CONCLUSIONS: Non-invasive scores based on LSM, spleen diameter and platelets predict clinical outcomes in PLWH. Composite biomarkers do not achieve higher prognostic performance compared to LSM alone.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Infecciones por VIH , Hipertensión Portal , Humanos , Cirrosis Hepática , Pronóstico , Bazo/diagnóstico por imagen , Plaquetas , Hígado/diagnóstico por imagen , Hígado/patología , Hipertensión Portal/complicaciones , Infecciones por VIH/complicaciones
7.
Am J Public Health ; 113(11): 1201-1209, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37733993

RESUMEN

Data System. The UK Department of Health and Social Care funded the REal-time Assessment of Community Transmission-2 (REACT-2) study to estimate community prevalence of SARS-CoV-2 IgG (immunoglobulin G) antibodies in England. Data Collection/Processing. We obtained random cross-sectional samples of adults from the National Health Service (NHS) patient list (near-universal coverage). We sent participants a lateral flow immunoassay (LFIA) self-test, and they reported the result online. Overall, 905 991 tests were performed (28.9% response) over 6 rounds of data collection (June 2020-May 2021). Data Analysis/Dissemination. We produced weighted estimates of LFIA test positivity (validated against neutralizing antibodies), adjusted for test performance, at local, regional, and national levels and by age, sex, and ethnic group and area-level deprivation score. In each round, fieldwork occurred over 2 weeks, with results reported to policymakers the following week. We disseminated results as preprints and peer-reviewed journal publications. Public Health Implications. REACT-2 estimated the scale and variation in antibody prevalence over time. Community self-testing and -reporting produced rapid insights into the changing course of the pandemic and the impact of vaccine rollout, with implications for future surveillance. (Am J Public Health. 2023;113(11):1201-1209. https://doi.org/10.2105/AJPH.2023.307381).


Asunto(s)
COVID-19 , Adulto , Humanos , COVID-19/diagnóstico , COVID-19/epidemiología , SARS-CoV-2 , Prevalencia , Estudios Transversales , Medicina Estatal , Anticuerpos Antivirales , Inmunoglobulina G , Inglaterra/epidemiología
8.
Am J Public Health ; 113(5): 545-554, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36893367

RESUMEN

Data System. The REal-time Assessment of Community Transmission-1 (REACT-1) Study was funded by the Department of Health and Social Care in England to provide reliable and timely estimates of prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection over time, by person and place. Data Collection/Processing. The study team (researchers from Imperial College London and its logistics partner Ipsos) wrote to named individuals aged 5 years and older in random cross-sections of the population of England, using the National Health Service list of patients registered with a general practitioner (near-universal coverage) as a sampling frame. We collected data over 2 to 3 weeks approximately every month across 19 rounds of data collection from May 1, 2020, to March 31, 2022. Data Analysis/Dissemination. We have disseminated the data and study materials widely via the study Web site, preprints, publications in peer-reviewed journals, and the media. We make available data tabulations, suitably anonymized to protect participant confidentiality, on request to the study's data access committee. Public Health Implications. The study provided inter alia real-time data on SARS-CoV-2 prevalence over time, by area, and by sociodemographic variables; estimates of vaccine effectiveness; and symptom profiles, and detected emergence of new variants based on viral genome sequencing. (Am J Public Health. 2023;113(5):545-554. https://doi.org/10.2105/AJPH.2023.307230).


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Inglaterra/epidemiología , Salud Pública , Medicina Estatal , Estudios Transversales
9.
PLoS Comput Biol ; 18(11): e1010724, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36417468

RESUMEN

BACKGROUND: Following rapidly rising COVID-19 case numbers, England entered a national lockdown on 6 January 2021, with staged relaxations of restrictions from 8 March 2021 onwards. AIM: We characterise how the lockdown and subsequent easing of restrictions affected trends in SARS-CoV-2 infection prevalence. METHODS: On average, risk of infection is proportional to infection prevalence. The REal-time Assessment of Community Transmission-1 (REACT-1) study is a repeat cross-sectional study of over 98,000 people every round (rounds approximately monthly) that estimates infection prevalence in England. We used Bayesian P-splines to estimate prevalence and the time-varying reproduction number (Rt) nationally, regionally and by age group from round 8 (beginning 6 January 2021) to round 13 (ending 12 July 2021) of REACT-1. As a comparator, a separate segmented-exponential model was used to quantify the impact on Rt of each relaxation of restrictions. RESULTS: Following an initial plateau of 1.54% until mid-January, infection prevalence decreased until 13 May when it reached a minimum of 0.09%, before increasing until the end of the study to 0.76%. Following the first easing of restrictions, which included schools reopening, the reproduction number Rt increased by 82% (55%, 108%), but then decreased by 61% (82%, 53%) at the second easing of restrictions, which was timed to match the Easter school holidays. Following further relaxations of restrictions, the observed Rt increased steadily, though the increase due to these restrictions being relaxed was offset by the effects of vaccination and also affected by the rapid rise of Delta. There was a high degree of synchrony in the temporal patterns of prevalence between regions and age groups. CONCLUSION: High-resolution prevalence data fitted to P-splines allowed us to show that the lockdown was effective at reducing risk of infection with school holidays/closures playing a significant part.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Estudios Transversales , Teorema de Bayes , Control de Enfermedades Transmisibles , SARS-CoV-2
10.
Semin Liver Dis ; 42(2): 159-172, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35189667

RESUMEN

Microelimination targets specific subpopulations and/or geographic settings for hepatitis C virus (HCV) elimination. This review reports on global HCV microelimination literature published from 2013 to 2020. Data were extracted from publications to report a score based on the four key components defining microelimination. Sustained virologic response (SVR) and treatment initiation proportions were calculated for each manuscript and grouped means of these estimates were compared depending on microelimination score and care setting. A total of 83% of the studies were from high-income settings and mainly included people who use drugs or those incarcerated. Among manuscripts, 18 had "low" microelimination scores, 11 had "high" scores, and the differences in mean proportion who initiated treatment and achieved SVR between low and high score groups were statistically significant. Microelimination can be a useful complementary strategy for driving engagement in HCV treatment and cure. Our analysis suggests that adhering to more of the core microelimination components can improve outcomes. This study is registered with Prospero, registration identification: CRD42020175211.


Asunto(s)
Hepatitis C Crónica , Hepatitis C , Antivirales/uso terapéutico , Hepacivirus , Hepatitis C/diagnóstico , Hepatitis C/tratamiento farmacológico , Hepatitis C/epidemiología , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Respuesta Virológica Sostenida
11.
Clin Infect Dis ; 75(1): e224-e233, 2022 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34549260

RESUMEN

BACKGROUND: The public health impact of the coronavirus disease 2019 (COVID-19) pandemic has motivated a rapid search for potential therapeutics, with some key successes. However, the potential impact of different treatments, and consequently research and procurement priorities, have not been clear. METHODS: Using a mathematical model of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission, COVID-19 disease and clinical care, we explore the public-health impact of different potential therapeutics, under a range of scenarios varying healthcare capacity, epidemic trajectories; and drug efficacy in the absence of supportive care. RESULTS: The impact of drugs like dexamethasone (delivered to the most critically-ill in hospital and whose therapeutic benefit is expected to depend on the availability of supportive care such as oxygen and mechanical ventilation) is likely to be limited in settings where healthcare capacity is lowest or where uncontrolled epidemics result in hospitals being overwhelmed. As such, it may avert 22% of deaths in high-income countries but only 8% in low-income countries (assuming R = 1.35). Therapeutics for different patient populations (those not in hospital, early in the course of infection) and types of benefit (reducing disease severity or infectiousness, preventing hospitalization) could have much greater benefits, particularly in resource-poor settings facing large epidemics. CONCLUSIONS: Advances in the treatment of COVID-19 to date have been focused on hospitalized-patients and predicated on an assumption of adequate access to supportive care. Therapeutics delivered earlier in the course of infection that reduce the need for healthcare or reduce infectiousness could have significant impact, and research into their efficacy and means of delivery should be a priority.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , SARS-CoV-2 , Costo de Enfermedad , Humanos , Pandemias/prevención & control , Preparaciones Farmacéuticas
12.
RNA ; 26(11): 1541-1556, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32747607

RESUMEN

Mechanisms underlying the ability of hepatitis C virus (HCV) to establish persistent infections and induce progressive liver disease remain poorly understood. HCV is one of several positive-stranded RNA viruses capable of establishing persistence in their immunocompetent vertebrate hosts, an attribute previously associated with formation of large-scale RNA structure in their genomic RNA. We developed novel methods to analyze and visualize genome-scale ordered RNA structure (GORS) predicted from the increasingly large data sets of complete genome sequences of HCV. Structurally conserved RNA secondary structure in coding regions of HCV localized exclusively to polyprotein ends (core, NS5B). Coding regions elsewhere were also intensely structured based on elevated minimum folding energy difference (MFED) values, but the actual stem-loop elements involved in genome folding were structurally poorly conserved, even between subtypes 1a and 1b. Dynamic remodeling was further evident from comparison of HCV strains in different host genetic backgrounds. Significantly higher MFED values, greater suppression of UpA dinucleotide frequencies, and restricted diversification were found in subjects with the TT genotype of the rs12979860 SNP in the IFNL4 gene compared to the CC (nonexpressing) allele. These structural and compositional associations with expression of interferon-λ4 were recapitulated on a larger scale by higher MFED values and greater UpA suppression of genotype 1 compared to genotype 3a, associated with previously reported HCV genotype-associated differences in hepatic interferon-stimulated gene induction. Associations between innate cellular responses with HCV structure and further evolutionary constraints represent an important new element in RNA virus evolution and the adaptive interplay between virus and host.


Asunto(s)
Hepacivirus/genética , Hepatitis C/genética , Interleucinas/genética , Polimorfismo de Nucleótido Simple , ARN Viral/química , Genoma Viral , Genotipo , Hepacivirus/clasificación , Hepatitis C/virología , Humanos , Modelos Moleculares , Conformación de Ácido Nucleico , Filogenia
13.
Vox Sang ; 117(12): 1360-1367, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36218235

RESUMEN

BACKGROUND AND OBJECTIVES: Adequate supplies of donor blood remain a major challenge in sub-Saharan Africa. This is exacerbated by a lack of confirmatory testing for transfusion-transmitted infections by blood transfusion services (BTS), leading to significant blood disposal owing to putatively high seroprevalence rates amongst Ugandan blood donors. We aimed to ascertain the false discovery rate of the Architect anti-hepatitis C virus (HCV) screening assay and categorize screen-reactive samples into three groups: presumed false positive, active and past infection, and develop an algorithm for confirmatory testing. MATERIALS AND METHODS: A total of 470 screen-reactive HCV blood donations were retested using the Architect anti-HCV assay, an alternative antibody test (SD Biosensor) and a core antigen (cAg) test. signal-to cut-off (S/CO) ratios and pre-analytical factors (centrifugation speed, haemolysis check, time between collection and testing) were recorded. Based on the S/CO ratio evaluation, we propose a testing algorithm to guide supplemental tests. RESULTS: The false discovery rate of the Architect anti-HCV assay was 0.84 as 395/470 (84%) screen-reactive samples had no evidence of HCV infection (SD Biosensor and cAg negative) (presumed false positive), 38/470 (8.1%) were antigenaemic, and 32/470 (6.8%) had evidence of past infection. The median S/CO ratios of the presumed false-positive and active infection samples were 1.8 and 17.3, respectively. The positive predictive value of HCV positivity in samples with ratios above 12 was 91.8%. On retesting, 104/470 (22.1%) samples became negative. CONCLUSION: The Architect anti-HCV assay has a very high false discovery rate in Ugandan BTSs, leading to excessive blood disposal. Pre-analytical factors likely contribute to this. An introduction of confirmatory testing using an algorithm based on S/CO ratio evaluation could limit unnecessary blood wastage and donor deferral.


Asunto(s)
Donantes de Sangre , Reacción a la Transfusión , Humanos , Estudios Seroepidemiológicos , Tamizaje Masivo , Hepacivirus , Anticuerpos contra la Hepatitis C , Sensibilidad y Especificidad
14.
BMC Infect Dis ; 22(1): 647, 2022 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-35896970

RESUMEN

BACKGROUND: Since the emergence of SARS-CoV-2, evolutionary pressure has driven large increases in the transmissibility of the virus. However, with increasing levels of immunity through vaccination and natural infection the evolutionary pressure will switch towards immune escape. Genomic surveillance in regions of high immunity is crucial in detecting emerging variants that can more successfully navigate the immune landscape. METHODS: We present phylogenetic relationships and lineage dynamics within England (a country with high levels of immunity), as inferred from a random community sample of individuals who provided a self-administered throat and nose swab for rt-PCR testing as part of the REal-time Assessment of Community Transmission-1 (REACT-1) study. During round 14 (9 September-27 September 2021) and 15 (19 October-5 November 2021) lineages were determined for 1322 positive individuals, with 27.1% of those which reported their symptom status reporting no symptoms in the previous month. RESULTS: We identified 44 unique lineages, all of which were Delta or Delta sub-lineages, and found a reduction in their mutation rate over the study period. The proportion of the Delta sub-lineage AY.4.2 was increasing, with a reproduction number 15% (95% CI 8-23%) greater than the most prevalent lineage, AY.4. Further, AY.4.2 was less associated with the most predictive COVID-19 symptoms (p = 0.029) and had a reduced mutation rate (p = 0.050). Both AY.4.2 and AY.4 were found to be geographically clustered in September but this was no longer the case by late October/early November, with only the lineage AY.6 exhibiting clustering towards the South of England. CONCLUSIONS: As SARS-CoV-2 moves towards endemicity and new variants emerge, genomic data obtained from random community samples can augment routine surveillance data without the potential biases introduced due to higher sampling rates of symptomatic individuals.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Inglaterra/epidemiología , Humanos , Filogenia , SARS-CoV-2/genética
15.
Clin Infect Dis ; 72(2): 233-238, 2021 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-32211763

RESUMEN

BACKGROUND: Modeling of the London hepatitis C virus (HCV) epidemic in men who have sex with men (MSM) and are living with human immunodeficiency virus (HIV) suggested that early access to direct-acting antiviral (DAA) treatment may reduce incidence. With high rates of linkage to care, microelimination of HCV within MSM living with HIV may be realistic ahead of 2030 World Health Organization targets. We examined trends in HCV incidence in the pre- and post-DAA eras for MSM living with HIV in London and Brighton, United Kingdom. METHODS: A retrospective cohort study was conducted at 5 HIV clinics in London and Brighton between 2013 and 2018. Each site reported all acute HCV episodes during the study period. Treatment timing data were collected. Incidence rates and reinfection proportion were calculated. RESULTS: A total of.378 acute HCV infections were identified, comprising 292 first infections and 86 reinfections. Incidence rates of acute HCV in MSM living with HIV peaked at 14.57/1000 person-years of follow-up (PYFU; 95% confidence interval [CI], 10.95-18.20) in 2015. Rates fell to 4.63/1000 PYFU (95% CI, 2.60 to 6.67) by 2018. Time from diagnosis to starting treatment declined from 29.8 (2013) to 3.7 months (2018). CONCLUSIONS: We observed a 78% reduction in the incidence of first HCV episode and a 68% reduction in overall HCV incidence since the epidemic peak in 2015, which coincides with wider access to DAAs in England. Further interventions to reduce transmission, including earlier access to treatment and for reinfection, are likely needed for microelimination to be achieved in this population.


Asunto(s)
Infecciones por VIH , Hepatitis C Crónica , Hepatitis C , Minorías Sexuales y de Género , Antivirales/uso terapéutico , Inglaterra , VIH , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Hepacivirus , Hepatitis C/tratamiento farmacológico , Hepatitis C/epidemiología , Hepatitis C/prevención & control , Hepatitis C Crónica/tratamiento farmacológico , Homosexualidad Masculina , Humanos , Incidencia , Londres/epidemiología , Masculino , Estudios Retrospectivos , Reino Unido/epidemiología
16.
Clin Infect Dis ; 72(9): e384-e393, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-32785665

RESUMEN

BACKGROUND: This study assesses acceptability and usability of home-based self-testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies using lateral flow immunoassays (LFIA). METHODS: We carried out public involvement and pilot testing in 315 volunteers to improve usability. Feedback was obtained through online discussions, questionnaires, observations, and interviews of people who tried the test at home. This informed the design of a nationally representative survey of adults in England using two LFIAs (LFIA1 and LFIA2) which were sent to 10 600 and 3800 participants, respectively, who provided further feedback. RESULTS: Public involvement and pilot testing showed high levels of acceptability, but limitations with the usability of kits. Most people reported completing the test; however, they identified difficulties with practical aspects of the kit, particularly the lancet and pipette, a need for clearer instructions and more guidance on interpretation of results. In the national study, 99.3% (8693/8754) of LFIA1 and 98.4% (2911/2957) of LFIA2 respondents attempted the test and 97.5% and 97.8% of respondents completed it, respectively. Most found the instructions easy to understand, but some reported difficulties using the pipette (LFIA1: 17.7%) and applying the blood drop to the cassette (LFIA2: 31.3%). Most respondents obtained a valid result (LFIA1: 91.5%; LFIA2: 94.4%). Overall there was substantial concordance between participant and clinician interpreted results (kappa: LFIA1 0.72; LFIA2 0.89). CONCLUSIONS: Impactful public involvement is feasible in a rapid response setting. Home self-testing with LFIAs can be used with a high degree of acceptability and usability by adults, making them a good option for use in seroprevalence surveys.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adulto , Anticuerpos Antivirales , Inglaterra , Humanos , Vigilancia de la Población , Autoevaluación , Estudios Seroepidemiológicos
17.
Clin Infect Dis ; 73(11): e4047-e4057, 2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-32766823

RESUMEN

BACKGROUND: Emerging evidence suggests ethnic minorities are disproportionately affected by coronavirus disease 2019 (COVID-19). Detailed clinical analyses of multicultural hospitalized patient cohorts remain largely undescribed. METHODS: We performed regression, survival, and cumulative competing risk analyses to evaluate factors associated with mortality in patients admitted for COVID-19 in 3 large London hospitals between 25 February and 5 April, censored as of 1 May 2020. RESULTS: Of 614 patients (median age, 69 [interquartile range, 25] years) and 62% male), 381 (62%) were discharged alive, 178 (29%) died, and 55 (9%) remained hospitalized at censoring. Severe hypoxemia (adjusted odds ratio [aOR], 4.25 [95% confidence interval {CI}, 2.36-7.64]), leukocytosis (aOR, 2.35 [95% CI, 1.35-4.11]), thrombocytopenia (aOR [1.01, 95% CI, 1.00-1.01], increase per 109 decrease), severe renal impairment (aOR, 5.14 [95% CI, 2.65-9.97]), and low albumin (aOR, 1.06 [95% CI, 1.02-1.09], increase per gram decrease) were associated with death. Forty percent (n = 244) were from black, Asian, and other minority ethnic (BAME) groups, 38% (n = 235) were white, and ethnicity was unknown for 22% (n = 135). BAME patients were younger and had fewer comorbidities. Although the unadjusted odds of death did not differ by ethnicity, when adjusting for age, sex, and comorbidities, black patients were at higher odds of death compared to whites (aOR, 1.69 [95% CI, 1.00-2.86]). This association was stronger when further adjusting for admission severity (aOR, 1.85 [95% CI, 1.06-3.24]). CONCLUSIONS: BAME patients were overrepresented in our cohort; when accounting for demographic and clinical profile of admission, black patients were at increased odds of death. Further research is needed into biologic drivers of differences in COVID-19 outcomes by ethnicity.


Asunto(s)
COVID-19 , Anciano , Estudios de Cohortes , Minorías Étnicas y Raciales , Femenino , Humanos , Londres/epidemiología , Masculino , Estudios Retrospectivos , SARS-CoV-2 , Medicina Estatal
18.
PLoS Med ; 18(9): e1003777, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34582457

RESUMEN

BACKGROUND: Rapid detection, isolation, and contact tracing of community COVID-19 cases are essential measures to limit the community spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We aimed to identify a parsimonious set of symptoms that jointly predict COVID-19 and investigated whether predictive symptoms differ between the B.1.1.7 (Alpha) lineage (predominating as of April 2021 in the US, UK, and elsewhere) and wild type. METHODS AND FINDINGS: We obtained throat and nose swabs with valid SARS-CoV-2 PCR test results from 1,147,370 volunteers aged 5 years and above (6,450 positive cases) in the REal-time Assessment of Community Transmission-1 (REACT-1) study. This study involved repeated community-based random surveys of prevalence in England (study rounds 2 to 8, June 2020 to January 2021, response rates 22%-27%). Participants were asked about symptoms occurring in the week prior to testing. Viral genome sequencing was carried out for PCR-positive samples with N-gene cycle threshold value < 34 (N = 1,079) in round 8 (January 2021). In univariate analysis, all 26 surveyed symptoms were associated with PCR positivity compared with non-symptomatic people. Stability selection (1,000 penalized logistic regression models with 50% subsampling) among people reporting at least 1 symptom identified 7 symptoms as jointly and positively predictive of PCR positivity in rounds 2-7 (June to December 2020): loss or change of sense of smell, loss or change of sense of taste, fever, new persistent cough, chills, appetite loss, and muscle aches. The resulting model (rounds 2-7) predicted PCR positivity in round 8 with area under the curve (AUC) of 0.77. The same 7 symptoms were selected as jointly predictive of B.1.1.7 infection in round 8, although when comparing B.1.1.7 with wild type, new persistent cough and sore throat were more predictive of B.1.1.7 infection while loss or change of sense of smell was more predictive of the wild type. The main limitations of our study are (i) potential participation bias despite random sampling of named individuals from the National Health Service register and weighting designed to achieve a representative sample of the population of England and (ii) the necessary reliance on self-reported symptoms, which may be prone to recall bias and may therefore lead to biased estimates of symptom prevalence in England. CONCLUSIONS: Where testing capacity is limited, it is important to use tests in the most efficient way possible. We identified a set of 7 symptoms that, when considered together, maximize detection of COVID-19 in the community, including infection with the B.1.1.7 lineage.


Asunto(s)
COVID-19/complicaciones , COVID-19/diagnóstico , Modelos Biológicos , Ageusia/diagnóstico , Ageusia/etiología , Ageusia/virología , Anosmia/diagnóstico , Anosmia/etiología , Anosmia/virología , Apetito , Área Bajo la Curva , COVID-19/virología , Escalofríos/diagnóstico , Escalofríos/etiología , Escalofríos/virología , Control de Enfermedades Transmisibles , Tos/diagnóstico , Tos/etiología , Tos/virología , Inglaterra , Reacciones Falso Positivas , Femenino , Fiebre/diagnóstico , Fiebre/etiología , Fiebre/virología , Humanos , Masculino , Tamizaje Masivo , Mialgia/diagnóstico , Mialgia/etiología , Mialgia/virología , Faringitis/diagnóstico , Faringitis/etiología , Faringitis/virología , Reacción en Cadena de la Polimerasa , SARS-CoV-2/genética , Medicina Estatal
19.
Hepatology ; 72(1): 7-18, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31652357

RESUMEN

BACKGROUND AND AIMS: Among treatment-naive individuals with chronic hepatitis C viral (HCV) infection and without cirrhosis, glecaprevir/pibrentasvir for 8 weeks is recommended. The aim of this analysis was to evaluate the efficacy of glecaprevir/pibrentasvir for 6 weeks in people with acute and recent HCV infection. APPROACH AND RESULTS: In this open-label, single-arm, multicenter, international pilot study, adults with recent HCV (duration of infection < 12 months) received glecaprevir/pibrentasvir 300/120 mg daily for 6 weeks. Primary infection was defined by first positive anti-HCV antibody and/or HCV RNA within 6 months of enrollment and either acute clinical hepatitis within the past 12 months (symptomatic seroconversion illness or alanine aminotransferase > 10 × upper limit of normal) or anti-HCV antibody seroconversion within 18 months. Reinfection was defined as new positive HCV RNA within 6 months of enrollment and evidence of prior spontaneous or treatment-induced clearance. The primary endpoint was sustained virologic response at 12 weeks posttreatment (SVR12). Thirty men (median age 43 years, 90% men who have sex with men) received treatment, of whom 77% (n = 23) were human immunodeficiency virus-positive, 47% (n = 14) had ever injected drugs, and 13% (n = 4) had HCV reinfection. The majority had HCV genotype 1 (83%, n = 25), followed by genotype 4 (10%, n = 3) and genotype 3 (7%, n = 2). At baseline, median estimated duration of infection was 29 weeks (range 13, 52) and median HCV RNA was 6.2 log10 IU/mL (range 0.9, 7.7). SVR12 in the intention-to-treat and per-protocol populations was achieved in 90% (27/30) and 96% (27/28), respectively. There was one case of relapse, and there were two cases of nonvirological failure (death, n = 1; loss to follow-up, n = 1). No treatment-related serious adverse events were seen. CONCLUSIONS: Glecaprevir/pibrentasvir for 6 weeks was highly effective among people with acute and recent HCV infection, supporting further evaluation of shortened-duration pan-genotypic therapy in this setting.


Asunto(s)
Bencimidazoles/uso terapéutico , Hepacivirus/genética , Hepatitis C/tratamiento farmacológico , Hepatitis C/virología , Pirrolidinas/uso terapéutico , Quinoxalinas/uso terapéutico , Sulfonamidas/uso terapéutico , Adulto , Anciano , Combinación de Medicamentos , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Factores de Tiempo , Resultado del Tratamiento
20.
Bull World Health Organ ; 99(9): 653-660, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34475602

RESUMEN

Poor control of cardiovascular disease accounts for a substantial proportion of the disease burden in developing countries, but often essential anticoagulant medicines for preventing strokes and embolisms are not widely available. In 2019, direct oral anticoagulants were added to the World Health Organization's WHO Model list of essential medicines. The aims of this paper are to summarize the benefits of direct oral anticoagulants for patients with cardiovascular disease and to discuss ways of increasing their usage internationally. Although the cost of direct oral anticoagulants has provoked debate, the affordability of introducing these drugs into clinical practice could be increased by: price negotiation; pooled procurement; competitive tendering; the use of patent pools; and expanded use of generics. In 2017, only 14 of 137 countries that had adopted national essential medicines lists included a direct oral anticoagulant on their lists. This number could increase rapidly if problems with availability and affordability can be tackled. Once the types of patient likely to benefit from direct oral anticoagulants have been clearly defined in clinical practice guidelines, coverage can be more accurately determined and associated costs can be better managed. Government action is required to ensure that direct oral anticoagulants are covered by national budgets because the absence of reimbursement remains an impediment to achieving universal coverage. Tackling cardiovascular disease with the aid of direct oral anticoagulants is an essential component of efforts to achieve the World Health Organization's target of reducing premature deaths due to noncommunicable disease by 25% by 2025.


L'absence de lutte efficace contre les maladies cardiovasculaires contribue grandement à la charge de morbidité pesant sur les pays en développement. Pourtant, les anticoagulants essentiels permettant d'éviter les accidents vasculaires cérébraux et les embolies sont souvent difficiles à obtenir. En 2019, les anticoagulants oraux directs ont été ajoutés à la Liste modèle des médicaments essentiels publiée par l'Organisation mondiale de la Santé. Le présent document vise à résumer les avantages des anticoagulants oraux directs pour les patients souffrant d'une maladie cardiovasculaire, et à évoquer les moyens d'encourager leur utilisation au niveau international. Bien que le coût des anticoagulants oraux directs ait fait débat, intégrer ces médicaments dans la pratique clinique les rendrait plus abordables grâce à diverses méthodes: négociation des prix; achats groupés; appels d'offres concurrentiels; communautés de brevets; et recours accru aux alternatives génériques. En 2017, seulement 14 des 137 pays ayant adopté des listes nationales de médicaments essentiels y avaient inclus des anticoagulants oraux directs. Ce chiffre pourrait augmenter rapidement si les problèmes de disponibilité et d'accessibilité peuvent être résolus. Dès que les profils des patients susceptibles d'être traités par des anticoagulants oraux directs sont clairement établis dans les directives de pratique clinique, la couverture peut être définie avec plus de précision et les dépenses correspondantes, mieux gérées. Les gouvernements doivent s'assurer que ces médicaments sont bien pris en compte dans les budgets nationaux, car l'absence de remboursement demeure un obstacle à la couverture maladie universelle. La lutte contre les maladies cardiovasculaires à l'aide des anticoagulants oraux directs est un élément essentiel des efforts destinés à atteindre l'objectif de l'OMS: faire baisser de 25% d'ici 2025 les décès prématurés dus aux maladies non transmissibles de 25% d'ici 2025.


El mal control de las enfermedades cardiovasculares representa una proporción importante de la carga de enfermedades en los países en desarrollo, y a menudo los medicamentos anticoagulantes esenciales para prevenir los accidentes cerebrovasculares y las embolias no son fácilmente accesibles. En 2019, los anticoagulantes orales directos se añadieron a la lista modelo de medicamentos esenciales de la Organización Mundial de la Salud. Los objetivos del presente artículo son resumir los beneficios de los anticoagulantes orales directos para los pacientes con enfermedades cardiovasculares y discutir las formas de aumentar su uso a nivel internacional. Aunque el coste de los anticoagulantes orales directos ha suscitado debate, la asequibilidad de introducir estos medicamentos en la práctica clínica podría aumentarse al: negociar precios; hacer adquisiciones conjuntas; hacer licitaciones competitivas; utilizar consorcios de patentes; y ampliar el uso de genéricos. En 2017, solo 14 de los 137 países que habían adoptado listas nacionales de medicamentos esenciales incluían un anticoagulante oral directo en sus listas. Este número podría aumentar rápidamente si se pueden abordar los problemas de disponibilidad y asequibilidad. Cuando los tipos de pacientes que pueden beneficiarse de los anticoagulantes orales directos se hayan definido claramente en las directrices de la práctica clínica, la cobertura podrá determinarse con mayor precisión y los costes asociados podrán gestionarse mejor. Es necesario que los gobiernos actúen para garantizar que los anticoagulantes orales directos estén cubiertos por los presupuestos nacionales, ya que la ausencia de reembolso sigue siendo un impedimento para lograr la cobertura universal. La lucha contra las enfermedades cardiovasculares con la ayuda de los anticoagulantes orales directos es un componente esencial de los esfuerzos por alcanzar el objetivo de la OMS de reducir las muertes prematuras debidas a enfermedades no transmisibles en un 25 % para 2025.


Asunto(s)
Anticoagulantes/economía , Costos de los Medicamentos , Medicamentos Esenciales/provisión & distribución , Medicamentos Genéricos/provisión & distribución , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Anticoagulantes/administración & dosificación , Anticoagulantes/uso terapéutico , Costos y Análisis de Costo , Medicamentos Esenciales/economía , Medicamentos Genéricos/economía , Costos de la Atención en Salud , Humanos
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