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1.
Vaccine ; 41(5): 1059-1066, 2023 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-36599736

RESUMEN

BACKGROUND: Hepatitis E virus (HEV) is a major cause of acute viral hepatitis worldwide and it contributes to considerable maternal and neonatal mortality and morbidity in many low-income countries like Bangladesh. A three-dose regimen of a vaccine against HEV (HEV 239) has shown promising results in China. The effects and safety of this vaccine in other populations and with different dosing regimens remains uncertain. OBJECTIVES: Investigate the immune response and safety of a two-dose regimen with the HEV 239 vaccine among healthy adults. Examine the feasibility of conducting a larger HEV 239 vaccine trial in rural Bangladesh. METHODS: One-hundred healthy men and non-pregnant women 16-39 years old were randomized in a 1:1 ratio to receive two doses of either the study (HEV) or control (Hepatitis B virus, HBV) vaccine (at 0, 1 month). Blood samples were collected at day 0, day 60 and 2 years after vaccination. The primary endpoints were the proportion and severity of adverse events up to 2 months after dose one and the longitudinal shift in anti-HEV IgG levels from day 0 to day 60 and 2 years after vaccination. RESULTS: Adverse events to HEV 239 were comparable to the control vaccine, mild in severity and resolved within one to nine days. All participants in the study group seroconverted and achieved high levels of HEV IgG antibodies that remained positive for two years in all but one. A T-cell response was detected one month after HEV 239 vaccination. CONCLUSION: Our results show that two doses of the HEV 239 vaccine produces broad and likely functional immune responses against HEV that remain for at least two years. The safety profile was acceptable and a phase four study of HEV 239 in rural Bangladesh is feasible. CLINICALTRIALS: gov Identifier: NCT02759991.


Asunto(s)
Virus de la Hepatitis E , Vacunas , Masculino , Femenino , Recién Nacido , Humanos , Adulto , Adolescente , Adulto Joven , Bangladesh , Proyectos Piloto , Anticuerpos Antihepatitis , Inmunoglobulina G , Método Doble Ciego , Inmunogenicidad Vacunal , Anticuerpos Antivirales
2.
Viruses ; 14(11)2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36423134

RESUMEN

Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis worldwide. In many low-income countries it causes large outbreaks and disproportionally affects pregnant women and their offspring. Surveillance studies to find effective preventive interventions are needed but are hampered by the lack of funding and infrastructure. Dried blood spots (DBS) offer an easier and more robust way to collect, transport, and store blood samples compared to plasma/serum samples, and could ease some of the barriers for such studies. In this study we optimize an HEV IgG ELISA for DBS samples and validate it on 300 paired DBS and plasma samples collected in rural areas of Bangladesh from participants in a HEV vaccine study. We demonstrate that HEV IgG in blood stored as DBS is stable for two months at up to 40 °C, and for five freeze-thaw cycles. The specificity was 97% and the overall sensitivity of the DBS assay was 81%. The sensitivity was higher in samples from vaccinated participants (100%) compared to previously infected participants (59%), reflecting a positive correlation between IgG titer and sensitivity. We found a strong correlation between DBS and plasma samples with an r2 of 0.90, but with a higher degree of difference between individual paired samples. Our study shows that DBS offers a stable alternative to plasma/serum for HEV IgG measurements and can facilitate serological studies, particularly in resource limited areas.


Asunto(s)
Virus de la Hepatitis E , Femenino , Humanos , Embarazo , Estudios de Factibilidad , Anticuerpos Antihepatitis , Pruebas Hematológicas , Inmunoglobulina G
3.
Viruses ; 15(1)2022 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-36680103

RESUMEN

HEV is the most common cause of acute hepatitis globally. This review summarizes the latest knowledge on the epidemiology, clinical characteristics, testing, and treatment of HEV infection. We also focused on Bangladesh to highlight the distinct challenges and the possible remedies. In low-income settings, the virus is mainly transmitted between people by fecal contamination of drinking water causing large outbreaks, and sporadic cases. The disease is usually mild and self-limiting acute hepatitis. Still, pregnant women and their offspring in low-income countries are at particular risk for severe disease, with up to 20% maternal mortality. Despite the high burden of the disease, HEV remains a relatively neglected virus, with detection hampered by costly tests and a lack of suitable treatments. Molecular PCR diagnostics, together with ELISA antibody tests, remain the preferred methods for diagnosis of HEV; however, rapid bedside diagnostics are available and could offer a practical alternative, especially in low-income countries. One vaccine (HEV 239) is only available in China and Pakistan, as efficacy against the other genotypes remains uncertain. The effectiveness trial conducted in Bangladesh might lead the way in gathering more efficacy data and could, together with improved surveillance and raised awareness, dramatically reduce the global burden of HEV.


Asunto(s)
Virus de la Hepatitis E , Hepatitis E , Humanos , Femenino , Embarazo , Virus de la Hepatitis E/genética , Bangladesh/epidemiología , Hepatitis E/diagnóstico , Hepatitis E/epidemiología , Hepatitis E/prevención & control , Brotes de Enfermedades , Genotipo , Enfermedad Aguda
4.
BMJ Open ; 10(1): e033702, 2020 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-31959609

RESUMEN

INTRODUCTION: Hepatitis E virus (HEV) is a leading cause of acute viral hepatitis in the developing world and is a public health problem, in particular among pregnant women, where it may lead to severe or fatal complications. A recombinant HEV vaccine, 239 (Hecolin; Xiamen Innovax Biotech, Xiamen, China), is licensed in China, but WHO calls for further studies to evaluate the safety and immunogenicity of this vaccine in vulnerable populations, and to evaluate protection in pregnancy. We are therefore conducting a phase IV trial to assess the effectiveness, safety and immunogenicity of the HEV 239 vaccine when given in women of childbearing age in rural Bangladesh, where HEV infection is endemic. METHODS AND ANALYSIS: Enrolment of a target of approximately 20 000 non-pregnant women, aged 16-39 years, started on 2 October 2017 in Matlab, Bangladesh. Sixty-seven villages were randomised by village at a 1:1 ratio to receive either the HEV vaccine or the control vaccine (hepatitis B vaccine). A 3-dose vaccination series at 0, 1 and 6 months is ongoing, and women are followed up for 24 months. The primary outcome is confirmed HEV disease among pregnant women. After vaccination, participants are requested to report information about clinical hepatitis symptoms. Participants who become pregnant are visited at their homes every 2 weeks to collect information about pregnancy outcome and to screen for clinical hepatitis. All suspected hepatitis cases undergo laboratory testing for diagnostic evaluation. The incidence of confirmed HEV disease among pregnant and non-pregnant women will be compared between the HEV vaccinated and control groups, safety and immunogenicity of the vaccine will also be evaluated. ETHICS AND DISSEMINATION: The protocol was reviewed and approved by the International Centre for Diarrhoeal Disease Research, Bangladesh Research Review Committee and Ethical Review Committee, and the Directorate General of Drug Administration in Bangladesh, and by the Regional Ethics Committee in Norway. This article is based on the protocol version 2.2 dated 29 June 2017. We will present the results through peer-reviewed publications and at international conferences. TRIAL REGISTRATION NUMBER: The trial is registered at clinicaltrials.gov with the registry name "Effectiveness Trial to Evaluate Protection of Pregnant Women by Hepatitis E Vaccine in Bangladesh" and the identifier NCT02759991.


Asunto(s)
Virus de la Hepatitis E/inmunología , Hepatitis E/prevención & control , Complicaciones Infecciosas del Embarazo/prevención & control , Población Rural , Vacunación/métodos , Vacunas Sintéticas/farmacología , Vacunas contra Hepatitis Viral/farmacología , Adolescente , Adulto , Bangladesh/epidemiología , Femenino , Estudios de Seguimiento , Hepatitis E/epidemiología , Humanos , Incidencia , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Pronóstico , Estudios Retrospectivos , Adulto Joven
5.
Liver Int ; 38(6): 1000-1009, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-28980394

RESUMEN

BACKGROUND & AIMS: Hepatitis D virus (HDV) infection is associated with a more severe outcome in patients with chronic hepatitis B (CHB); however, little is known about the presence of HDV in sub-Saharan Africa. We aimed to determine the prevalence of HDV infection, as well as its clinical, biological and virological characteristics, in a large CHB cohort in Ethiopia. METHODS: In total, 1267 HIV-negative CHB patients at St. Paul's Hospital Millennium Medical College in Addis Ababa were screened for anti-HDV antibodies using ELISA assays. Confirmed positive samples were further tested for HDV RNA using a consensus commercial real-time RT-PCR assay. HDV genotypes were also determined for RNA-positive samples by nucleotide sequencing followed by phylogenetic analyses. Demographical, clinical and biological data from patients were recorded and compared based on HDV RNA results. RESULTS: Most patients (n = 748, 59.0%) were men, and the median age was 31 years (interquartile range 26-40). Anti-HDV antibodies were detected in 19 individuals (1.5%), 12 of whom were HDV RNA-positive with a viral load ranging from <2 to >8 log 10 IU/mL. All strains were genotype 1. HDV RNA-positive patients were more likely to have significant liver fibrosis (63.6% vs 24.7%, P = .007) and cirrhosis (45.5% vs 16.4%, P = .024). CONCLUSIONS: HDV infection is rare in Ethiopia but is associated with more advanced liver fibrosis.


Asunto(s)
Coinfección/virología , Hepatitis B Crónica/complicaciones , Hepatitis D/epidemiología , Virus de la Hepatitis Delta/genética , Cirrosis Hepática/virología , Adolescente , Adulto , Estudios de Cohortes , Coinfección/mortalidad , Ensayo de Inmunoadsorción Enzimática , Etiopía/epidemiología , Femenino , Anticuerpos Antihepatitis/sangre , Hepatitis D/mortalidad , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Carga Viral , Adulto Joven
6.
Eur J Public Health ; 28(4): 720-724, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29237007

RESUMEN

Background: Evidence has shown that Hepatitis E virus (HEV) genotype 3 is autochthonous in industrialized countries due to zoonotic transmission through direct contact or consumption of raw or undercooked meat from domestic swine or wild boar. As there is lack of data on seroprevalence of HEV in the general Portuguese population, a wide survey was conducted as part of the HEPeCONTROL project (60DT2), under EEA grants funding. Methods: Sera from a representative sample of the Portuguese population (n = 1656) at different geographic locations (30 territorial units), and age (0-99 years) were collected between July 2015 and February 2016. The sera were tested for the presence of anti-HEV IgG and IgM by EIA using one of the two most commonly used commercial immunoassays in Europe. Results: The overall HEV IgG seroprevalence was found to be 16.3% increasing with age (P < 0.05) from 0.6% in the 0-9 years group to 30.1% in people older than 70 years. The seroprevalence also varied geographically with generally higher seropositivities (25-30%) in the most rural areas of Portugal. However, the geographical differences were not statistically significant (P > 0.05). Out of 1656 samples, 8 were positive for anti-HEV IgM indicating current of recent HEV infection but no significant differences were found concerning age groups, regions and sex. Conclusions: The present nation-wide survey provides insight in the epidemiology of HEV in Portugal and confirms that HEV is endemic in the Portuguese population.


Asunto(s)
Biomarcadores/sangre , Anticuerpos Antihepatitis/sangre , Virus de la Hepatitis E/aislamiento & purificación , Hepatitis E/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Portugal/epidemiología , Estudios Seroepidemiológicos , Adulto Joven
7.
PLoS One ; 11(11): e0166201, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27820845

RESUMEN

BACKGROUND & AIMS: Hepatitis B virus (HBV) quantification is essential in the management of chronic hepatitis B, both to determine treatment eligibility and in the monitoring of treatment effect. This test, however, is rarely available in resource-limited settings due to high costs and stringent requirements for shipment and storage of plasma. Dried Blood Spots (DBS) can be a convenient alternative to plasma, but its use for HBV monitoring has not been investigated under real-life conditions in Africa. METHODS: The performance of DBS in HBV quantification was investigated using a modified commercial test (Abbott RealTime HBV assay). Paired DBS and plasma samples were collected from an HBV positive cohort in Addis Ababa, Ethiopia. DBS were stored at ambient temperature for 4-39 days before shipment to the laboratory. RESULTS: Twenty-six paired samples were selected covering the total range of quantification, from 2.14 log IU/ml to >7 log IU/ml. HBV was detected in 21 of 21 (100%) DBS from patients with a corresponding plasma viral load above 2.70 log IU/ml. The mean difference between plasma and DBS was 0.59 log IU/ml, and the correlation was strong (R2 = 0.92). In stability studies there was no significant change in DBS viral load after storage at room temperature for up to 12 weeks. CONCLUSIONS: This study suggests that DBS can be a feasible and reliable alternative to plasma for quantification of HBV in resource-limited settings. DBS can expand access to antiviral treatment for patients in low- and middle-income countries.


Asunto(s)
Recolección de Muestras de Sangre/métodos , Sangre/virología , Virus de la Hepatitis B/aislamiento & purificación , Manejo de Especímenes/métodos , Carga Viral/métodos , África , Desecación/métodos , Recursos en Salud , Hepatitis B/sangre , Hepatitis B/virología , Humanos , Plasma/virología , Sensibilidad y Especificidad
9.
BMC Infect Dis ; 16: 17, 2016 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-26774897

RESUMEN

BACKGROUND: The discovery of autochthonous hepatitis E in industrialized countries has changed the understanding of hepatitis E virus (HEV) infection in these regions, now known to be mainly due to zoonotic transmission of genotype 3. The foodborne route of transmission via consumption of contaminated meat from HEV infected pigs is well documented as well as the direct occupational exposure to animal reservoirs. Accumulating evidence also points to an emerging potential threat to blood safety after the identification of viremic blood donors and the documentation of HEV-contaminated blood or blood products. Moreover, the origin of several iatrogenic cases remains unclear and porcine-derived pharmaceutic products have been suspected as a cause. Severe morbidity following HEV infection in patients receiving immunosuppressive therapy and in those with severe immunodeficiency from other causes has been recently recognized as a serious consequence of this infection in industrialized countries. In Portugal no large-scale HEV seroprevalence study has been undertaken, no professional risk groups have been identified, and the risk of blood donation from HEV silent infected donors is unknown. The present paper describes seroepidemiological and molecular approaches to answer these questions. METHODS/DESIGN: To address these issues a study protocol was designed that will approach: i) the seroprevalence of HEV among the Portuguese general population; ii) HEV infection among butchers and slaughterhouse workers (occupational risk); iii) the silent HEV infection in Portuguese blood donors (HEV transfusion-associated risk); iv) the potential HEV contamination of porcine-derived pharmaceutical products. Commercial enzyme immunoassays and real-time/conventional RT-PCR assays will be used. DISCUSSION: This study is the first evaluation of the seroepidemiological status to HEV infection of the Portuguese population, the first to potentially identify professional risk groups, and to evaluate the safety of blood and blood products and porcine-derived pharmaceutics in Portugal. It will generate valuable data applicable for preventive and control measures against HEV infection (e.g., introduction of systematic screening of blood donors, control of blood products or porcine derived pharmaceutical products), thus helping to manage the burden of this viral disease.


Asunto(s)
Virus de la Hepatitis E/fisiología , Hepatitis E/epidemiología , Enfermedades Profesionales/epidemiología , Animales , Anticuerpos Antivirales/sangre , Donantes de Sangre , Seguridad de la Sangre , Protocolos Clínicos , Genotipo , Hepatitis E/transmisión , Hepatitis E/virología , Virus de la Hepatitis E/genética , Virus de la Hepatitis E/aislamiento & purificación , Humanos , Enfermedades Profesionales/inmunología , Enfermedades Profesionales/virología , Portugal/epidemiología , Salud Pública , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Seroepidemiológicos , Sus scrofa , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/virología , Reacción a la Transfusión , Viremia/etiología
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