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1.
Int J Mol Sci ; 22(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33672018

RESUMO

Hepatitis B is a major global health challenge. In the absence of an effective treatment for the disease, hepatitis B vaccines provide protection against the viral infection. However, some individuals do not have positive immune responses after being vaccinated with the hepatitis B vaccines available in the market. Thus, it is important to develop a more protective vaccine. Previously, we showed that hepatitis B virus (HBV) 'a' determinant (aD) displayed on the prawn nodavirus capsid (Nc) and expressed in Spodoptera frugiperda (Sf9) cells (namely, Nc-aD-Sf9) self-assembled into virus-like particles (VLPs). Immunisation of BALB/c mice with the Nc-aD-Sf9 VLPs showed significant induction of humoral, cellular and memory B-cell immunity. In the present study, the biophysical properties of the Nc-aD-Sf9 VLPs were studied using dynamic light scattering (DLS) and circular dichroism (CD) spectroscopy. Enzyme-linked immunosorbent assay (ELISA) was used to determine the antigenicity of the Nc-aD-Sf9 VLPs, and multiplex ELISA was employed to quantify the cytokine response induced by the VLPs administered intramuscularly into BALB/c mice (n = 8). CD spectroscopy of Nc-aD-Sf9 VLPs showed that the secondary structure of the VLPs predominantly consisted of beta (ß)-sheets (44.8%), and they were thermally stable up to ~52 °C. ELISA revealed that the aD epitope of the VLPs was significantly antigenic to anti-HBV surface antigen (HBsAg) antibodies. In addition, multiplex ELISA of serum samples from the vaccinated mice showed a significant induction (p < 0.001) of IFN-γ, IL-4, IL-5, IL-6, IL-10, and IL-12p70. This cytokine profile is indicative of natural killer cell, macrophage, dendritic cell and cytotoxic T-lymphocyte activities, which suggests a prophylactic innate and adaptive cellular immune response mediated by Nc-aD-Sf9 VLPs. Interestingly, Nc-aD-Sf9 induced a more robust release of the aforementioned cytokines than that of Nc-aD VLPs produced in Escherichia coli and a commercially used hepatitis B vaccine. Overall, Nc-aD-Sf9 VLPs are thermally stable and significantly antigenic, demonstrating their potential as an HBV vaccine candidate.


Assuntos
Proteínas do Capsídeo/imunologia , Citocinas/metabolismo , Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Epitopos Imunodominantes/imunologia , Nodaviridae/imunologia , Transdução de Sinais/imunologia , Vacinação/métodos , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Anticorpos/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/administração & dosagem , Temperatura Alta , Camundongos , Camundongos Endogâmicos BALB C , Células Sf9 , Spodoptera , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem
2.
Vaccine ; 39(5): 780-785, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33414050

RESUMO

Although the direct health impact of Coronavirus disease (COVID-19) pandemic on child health is low, there are indirect impacts across many aspects. We compare childhood vaccine uptake in three types of healthcare facilities in Singapore - public primary care clinics, a hospital paediatric unit, and private paediatrician clinics - from January to April 2020, to baseline, and calculate the impact on herd immunity for measles. We find a 25.6% to 73.6% drop in Measles-Mumps-Rubella (MMR) uptake rates, 0.4 - 10.3% drop for Diphtheria-Tetanus-Pertussis-inactivated Polio-Haemophilus influenza (5-in-1), and 8.0-67.8% drop for Pneumococcal conjugate vaccine (PCV) across all 3 sites. Consequent herd immunity reduces to 74-84% among 12-month- to 2-year-olds, well below the 95% coverage that is protective for measles. This puts the whole community at risk for a measles epidemic. Public health efforts are urgently needed to maintain efficacious coverage for routine childhood vaccines during the COVID-19 pandemic.


Assuntos
/epidemiologia , Saúde da Criança/estatística & dados numéricos , Saúde Pública/normas , Cobertura Vacinal/estatística & dados numéricos , /prevenção & controle , Pré-Escolar , Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Vacinas Anti-Haemophilus/administração & dosagem , Vacinas contra Hepatite B/administração & dosagem , Humanos , Imunidade Coletiva , Esquemas de Imunização , Lactente , Vacina contra Sarampo-Caxumba-Rubéola/administração & dosagem , Vacina Antipólio de Vírus Inativado/administração & dosagem , Estudos Retrospectivos , Singapura/epidemiologia
3.
Bull Cancer ; 108(1): 90-101, 2021 Jan.
Artigo em Francês | MEDLINE | ID: mdl-33358507

RESUMO

Hepatitis B Virus (HBV) chronic infection contributes to a high risk of hepatocellular cancer (HCC) development. HBV is a strong cancer inducer, due to natural history of infection, virological characteristics and viral DNA integrations events in host genome. Prolonged infection and high viral loads, particularly frequent in patients infected in childhood, are risk factors of HCC development for patients with HBV chronic infection. A HBV vaccine, based on immunization against the surface protein HBs, showed a strong efficacy to prevent chronic HBV infection. The development of universal neonatal vaccination programmes contributed to the decrease of HBV chronic infection incidence in children of high endemic areas. Although HBs antibodies levels diminished years after vaccination, HBV neonatal vaccination programmes led to a lower incidence of chronic HBV infection among young adults. The decrease of HBV chronic infection incidence was associated to a reduction of HCC incidence in children and young adults from areas with a high prevalence of HBV infection.


Assuntos
Carcinoma Hepatocelular/prevenção & controle , Vacinas contra Hepatite B/administração & dosagem , Hepatite B/prevenção & controle , Neoplasias Hepáticas/prevenção & controle , Adulto , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/virologia , Criança , Hepatite B/epidemiologia , Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/fisiologia , Humanos , Incidência , Lactente , Recém-Nascido , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/virologia , Fatores de Risco , Replicação Viral , Adulto Jovem
4.
Arch. prev. riesgos labor. (Ed. impr.) ; 23(4): 430-442, oct.-dic. 2020. tab
Artigo em Espanhol | IBECS | ID: ibc-197174

RESUMO

OBJETIVO: Estimar la prevalencia de inmunización frente al virus de la Hepatitis B del personal sanitario, vinculado a los Departamentos de Salud de Torrevieja y Elche-Crevillente, de la Comunidad Valenciana. MÉTODOS: Estudio descriptivo transversal en todos los trabajadores sanitarios de dos departamentos de Salud. Obtenida la muestra se identificó los niveles de anticuerpos de superficie del virus de la Hepatitis B a través de los resultados serológicos ubicados en las historias clínicas. Se consideró inmunizado a títulos de anti-HBs ≥ 10 mlU/ml. Las variables analizadas fueron categorizadas según: Departamento; Género; Edad (18-34; 35-49; > 50 años); categoría profesional (facultativos/Enfermería/Otro personal sanitario/Personal no sanitario); Servicio riesgo contagio (Si/No); Inmunidad (≥ 10 mlU/ml / < 10 mlU/ml / No Dato) y Vacunacion sistemática anti-HBs según fecha nacimiento (Si/No). RESULTADOS: El personal estudiado ascendió a 2674. Predominó el género femenino 68,8%, el grupo de edad 35-49 años, 52,8%, y la categoría profesional de Enfermería, 32,2%. Un 74,9% de los resultados serológicos identificaron niveles de protección anti-HBs, frente al 11,3% no inmune, y un 13,8% que no disponían de información. Del personal con información serológica (2306), obtuvieron porcentajes de no protección más elevadas la categoría masculina, 17,8%. Los niveles de protección fueron inversamente proporcionales según la variable edad, menor inmunidad a mayor edad. El personal no sanitario y los facultativos arrojaron niveles de protección más bajos, 36,9% y 11,1% respectivamente. CONCLUSIONES: A pesar de identificarse una inmunidad elevada, el porcentaje de no inmunizados y de ausencia de información inmunológica plantea la necesidad de implementar nuevas estrategias de comunicación dirigidas a este colectivo


OBJECTIVE: To estimate the prevalence of immunity against Hepatitis B virus among all healthcare workers linked to the Departments of Public Health in Torrevieja and Elx-Crevillent, two municipalities in the Valencian Community, Spain. Methods: Cross-sectional descriptive study of healthcare workers in two different public health departments. Once the sample was obtained, the anti-hepatitis B surface antibody (anti-HBsAb) levels were abstracted based on serological test results recorded in the workers’ medical records. Titers of anti-HBsAB ≥ 10 mlU / ml were considered as evience of immunity. The variables analyzed were classified by department, gender, age (18-34; 35-49; ≥ 50 years); professional category (physicians / nursing / other health personnel / non-health personnel); service at risk of contagion (Yes / No); immunity (≥ 10 mlU/ml, < 10 mlU/ml, missing) and systematic anti-HBs vaccination by date of birth (Yes / No). RESULTS: The study population consisted of 2674 workers. The highest proportions of workers were female (68.8%), between 35 and 49 years of age (52.8%), and employed in nursing,(32.2%). Overall, 74.9% of employees had evidence of hepatitis B immunity, 11.3% had no inmunity, and 13.8% was missing information on serology. Among those employees with serological information (n = 2306), lack of immunity was highest among males (17.8%). Protective titers were inversely proportional to age, with the lowest titers being found in the oldest age groups. Non-healthcare personnel and physicians also had lower levels of protection (36.9% and 11.1%, respectively). CONCLUSIONS: Despite identifying high levels of immunity among healthcare workers, the percentages of non-immunized employees and those lacking immunological information underscores the need to implement new communication strategies aimed at these at-risk groups


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Pessoal de Saúde/estatística & dados numéricos , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vacinas contra Hepatite B/imunologia , Vacinação/estatística & dados numéricos , Estudos Transversais , Hepatite B/sangue , Hepatite B/imunologia , Anticorpos Anti-Hepatite B/imunologia , Vacinas contra Hepatite B/administração & dosagem , Saúde Pública , Características de Residência , Espanha/epidemiologia
5.
Am J Gastroenterol ; 115(11): 1797-1798, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33156097

RESUMO

Prevention of hepatitis B (HBV) infection is particularly important for patients with inflammatory bowel disease because of risks of HBV reactivation on immunosuppressive therapies. However, immune responses to standard HBV vaccination regimens are suboptimal. Chaparro et al. compared immune responses to 2 vaccines, an adjuvanted HBV vaccine (Fendrix) and double-dosed standard vaccine (Engerix-B) using an accelerated, 4-dose regimen (0, 1, 2, and 6 months). Although the study did not demonstrate superiority of one vaccine over another, several lessons can be derived regarding immune response to vaccinations among patients with inflammatory bowel disease, including the need to consider nonstandard regimens for patients on immunosuppression. These lessons can be translated broadly, including to a potential future severe acute respiratory syndrome coronavirus 2 vaccine when one becomes available.


Assuntos
Infecções por Coronavirus/prevenção & controle , Vacinas contra Hepatite B/administração & dosagem , Hepatite B/prevenção & controle , Doenças Inflamatórias Intestinais/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/administração & dosagem , Betacoronavirus , Humanos
6.
PLoS One ; 15(10): e0238987, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33052919

RESUMO

INTRODUCTION: One third of the world population has been exposed to hepatitis B virus and an estimated 257 million people are chronically infected. The main route of hepatitis B virus (HBV) infection is vertical transmission. Post exposure prophylaxis is recommended by world health organization to have free Hepatitis B infection by 2030. OBJECTIVE: The main purpose of this research project was to assess Hepatitis B virus post exposure prophylaxis coverage, rate of vertical transmission and factors among exposed newborns delivered at Arsi zone health institution. METHODS: A cross-sectional study was conducted in Arsi zone health institutions among hepatitis B virus exposed newborns delivered at Arsi zone health institutions from January 2018 to September 2019. Systematic sampling technique was used to select 422 exposed newborns into the study. A pre-tested structured questionnaire and checklist were used to collect relevant data. Data was entered and cleaned using epidata7 & analyzed using SPSS version 25 software package. Both bivariate and multivariate analyses was carried out to identify associations. Odds ratio with 95% CI and P-value <0.05 was considered statistically significant. RESULTS: The study revealed that among 401 exposed newborns only 83(20.7%), have been administered post exposure prophylaxis. But vertical transmission of hepatitis B virus (HBV) was observed in 32.4% (27.9%-36.9%) exposed newborns. Antenatal (ANC) attendance (AOR = .40, 95%CI = .23-.69), Instrumental delivery (AOR = 4.18, 95%CI = 2.05-8.51) HIV coinfection (AOR = 9.7, 95%CI = 4.37-21.34), Post exposure Prophylaxis (AOR = .20, 95%CI = .08-.50) and Knowledge on HBV (AOR = .27, 95%CI = .14-.53) are significant predictors of HBV vertical transmission. CONCLUSION: Magnitude of HBV post exposure prophylaxis coverage is very low while Rate of vertical transmission is high. Antenatal attendance, Instrumental delivery, Post exposure Prophylaxis and Knowledge on hepatitis B virus transmission are significant predictors of HBV vertical transmission.


Assuntos
Hepatite B/prevenção & controle , Hepatite B/transmissão , Transmissão Vertical de Doença Infecciosa/prevenção & controle , Profilaxia Pós-Exposição/métodos , Complicações Infecciosas na Gravidez/epidemiologia , Adolescente , Adulto , Estudos Transversais , Etiópia/epidemiologia , Feminino , Hepatite B/epidemiologia , Antígenos de Superfície da Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Humanos , Imunoglobulinas/administração & dosagem , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Gravidez , Fatores de Risco , Adulto Jovem
7.
BMC Public Health ; 20(1): 1219, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778075

RESUMO

BACKGROUND: Migrant workers are a susceptible population to the hepatitis b virus (HBV) and a vulnerable spot in China's immunization procedures. There is no free HBV immunization program for migrant workers in China, so understanding migrant workers' motivation to receive the HBV vaccine is the first step in designing effective immunization policies. METHODS: A fully specified protection motivation theory (PMT) model of HBV vaccination intention among migrant workers was specified. Data were collected through a cross-sectional survey of 406 migrant workers in three migrant-dense industries in Tianjin, China. Principal component factor analysis was used to produce PMT factors and nested binary logistic regression modeling was applied to assess the associations between protection motivation and HBV vaccination intention of migrant workers. RESULTS: The nested binary logistic regression model suggested that the severity factor and self-efficacy factor were positively related to HBV vaccination intention (OR = 2.15, 95% CI: 1.25-3.71; OR = 2.75, 95% CI: 1.62-4.66) while the response costs was negatively related to the HBV vaccination motivation (OR = 0.50, 95% CI: 0.29-0.83). The socio-demographic variables showed that younger, married and good self-rated health status participants were statistically associated with the intention of taking the HBV vaccine. Sex, education level and income group were not significantly associated with vaccination intention. The migrant-industry variables showed that migrant location had a strong effect on migrant workers' vaccination intention. CONCLUSION: Socio-demographic, migrant-industry variables and PMT factors (severity, self-efficacy and response costs) were statistically associated with migrant workers' intention to vaccinate. Our results suggest that health policy makers should provide more information to migrants on HBV severity; inform migrant workers on where, when and how to get the HBV vaccine; tap into work organizations as a location for vaccinations; and identify migrant worker subgroups for targeted interventions.


Assuntos
Vacinas contra Hepatite B/administração & dosagem , Hepatite B/prevenção & controle , Intenção , Motivação , Migrantes/psicologia , Vacinação/psicologia , Adolescente , Adulto , Idoso , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Migrantes/estatística & dados numéricos , Adulto Jovem
8.
PLoS One ; 15(8): e0237525, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32776972

RESUMO

Hepatitis B is a global epidemic that requires carefully orchestrated vaccination initiatives in geographical regions of medium to high endemicity to reach the World Health Organization's elimination targets by 2030. This study compares two widely-used deterministic hepatitis B models-the Imperial HBV model and the CDA Foundation's PRoGReSs-based on their predicted outcomes in four countries. The impact of scaling up of the timely birth dose of the hepatitis B vaccine is also investigated. The two models predicted largely similar outcomes for the impact of vaccination programmes on the projected numbers of new cases and deaths under high levels of the infant hepatitis B vaccine series. However, scenarios for the scaling up of the infant hepatitis B vaccine series had a larger impact in the PRoGReSs model than in the Imperial model due to the infant vaccine series directly leading to the reduction of perinatal transmission in the PRoGReSs model, but not in the Imperial model. Meanwhile, scaling up of the timely birth dose vaccine had a greater impact on the outcomes of the Imperial hepatitis B model than in the PRoGReSs model due to the greater protection that the birth dose vaccine confers to infants in the Imperial model compared to the PRoGReSs model. These differences underlie the differences in projections made by the models under some circumstances. Both sets of assumptions are consistent with available data and reveal a structural uncertainty that was not apparent in either model in isolation. Those relying on projections from models should consider outputs from both models and this analysis provides further evidence of the benefits of systematic model comparison for enhancing modelling analyses.


Assuntos
Vacinas contra Hepatite B/administração & dosagem , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/prevenção & controle , Programas de Imunização/estatística & dados numéricos , Transmissão Vertical de Doença Infecciosa/prevenção & controle , Modelos Estatísticos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Saúde Global , Hepatite B/epidemiologia , Hepatite B/virologia , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Gravidez , Organização Mundial da Saúde , Adulto Jovem
9.
Arch Virol ; 165(10): 2361-2365, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32743697

RESUMO

In this study, we investigated the seroprevalence of anti-hepatitis D virus (HDV) antibodies in hepatitis B surface antigen (HBsAg)-positive children after 25 years of obligatory vaccination of infants against hepatitis B virus. This cross-sectional study included 120 treatment-naïve HBsAg-positive children, with a male-to-female ratio of 1.8:1 and a mean age of 7.8 ± 3.8 years (range, 1-17 years). Mothers were positive for HBsAg in 96.6% of the cases. HBeAg-positive chronic infection was observed in 60% of the cases, HBeAg-positive chronic hepatitis in 12.5%, and HBeAg-negative chronic infection in 26.7%. Anti-HDV antibodies were not detected in any of the cases. Thus, there is a lack of anti-HDV antibodies in HBsAg-positive children, despite the current burden in adults.


Assuntos
Anticorpos Anti-Hepatite/sangue , Antígenos de Superfície da Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Vírus da Hepatite B/imunologia , Hepatite B/epidemiologia , Hepatite D Crônica/epidemiologia , Vírus Delta da Hepatite/imunologia , Adolescente , Criança , Pré-Escolar , Coinfecção , Estudos Transversais , Egito/epidemiologia , Feminino , Hepatite B/imunologia , Hepatite B/prevenção & controle , Hepatite B/virologia , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/patogenicidade , Hepatite D Crônica/sangue , Hepatite D Crônica/imunologia , Hepatite D Crônica/virologia , Vírus Delta da Hepatite/patogenicidade , Humanos , Lactente , Masculino , Estudos Soroepidemiológicos
11.
MMWR Morb Mortal Wkly Rep ; 69(30): 988-992, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32730237

RESUMO

In 2015, the World Health Organization (WHO) South-East Asia Region (SEAR)* reported an estimated 40 million persons living with chronic hepatitis B virus (HBV) infection and 285,000 deaths from complications of chronic infection, cirrhosis, and hepatocellular carcinoma (1). Most chronic HBV infections, indicated by the presence of hepatitis B surface antigen (HBsAg) on serologic testing, are acquired in infancy through perinatal or early childhood transmission (2). To prevent perinatal and childhood infections, WHO recommends that all infants receive at least 3 doses of hepatitis B vaccine (HepB), including a timely birth dose (HepB-BD)† (1). In 2016, the SEAR Immunization Technical Advisory Group endorsed a regional hepatitis B control goal with a target of achieving hepatitis B surface antigen (HBsAg) seroprevalence of ≤1% among children aged ≥5 years by 2020, which is in line with the WHO Global Health Sector Strategy on Viral Hepatitis 2016-2021 (2,3). The South-East Asia Regional Vaccine Action Plan 2016-2020 (SEARVAP) (4) identified the acceleration of hepatitis B control as one of the eight regional goals for immunization. The plan outlined four main strategies for achieving hepatitis B control: 1) achieving ≥90% coverage with 3 doses of HepB (HepB3), 2) providing timely vaccination with a HepB birth dose (HepB-BD), 3) providing catch-up vaccination of older children, and 4) vaccinating adult populations at high risk and health care workers (1,4). In 2019, SEAR established a regional expert panel on hepatitis B to assess countries' HBV control status. This report describes the progress made toward hepatitis B control in SEAR during 2016-2019. By 2016, all 11 countries in the region had introduced HepB in their national immunization programs, and eight countries had introduced HepB-BD. During 2016-2019, regional HepB3 coverage increased from 89% to 91%, and HepB-BD coverage increased from 34% to 54%. In 2019, nine countries in the region achieved ≥90% HepB3 coverage, and three of the eight countries that provide HepB-BD achieved ≥90% HepB-BD coverage. By December 2019, four countries had been verified to have achieved the hepatitis B control goal. Countries in the region can make further progress toward hepatitis B control by using proven strategies to improve HepB-BD and HepB3 coverage rates. Conducting nationally representative hepatitis B serosurveys among children will be key to tracking and verifying the regional control targets.


Assuntos
Hepatite B Crônica/prevenção & controle , Ásia Sudeste/epidemiologia , Criança , Pré-Escolar , Feminino , Objetivos , Antígenos de Superfície da Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Hepatite B Crônica/epidemiologia , Humanos , Programas de Imunização , Lactente , Recém-Nascido , Gravidez , Estudos Soroepidemiológicos , Organização Mundial da Saúde
12.
BMC Infect Dis ; 20(1): 528, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32698884

RESUMO

BACKGROUND: Hepatitis B virus (HBV) infection is one of the major public health problems worldwide. Limited information exists about the epidemiology of HBV infection in Ethiopia. This study aimed to assess sero-prevalence of HBV markers and associated factors in children living in Hawassa City, southern Ethiopia. METHODS: A community-based cross-sectional study was conducted among 471 children in Hawassa City, southern Ethiopia from May to September, 2018. A total of 471 children were included in the study using a multistage sampling technique. Data on demographic and risk factors were gathered using structured questionnaires. Blood samples were collected and sera were screened for hepatitis B surface antigen (HBsAg), antibody to core antigen (anti-HBc), and antibody against surface antigen (anti-HBs) using enzyme-linked immunosorbent assay. RESULTS: The sero-prevalence of HBsAg, anti-HBc, and anti-HBs markers among children were 4.4, 19.5 and 20.0%, respectively. Children at higher risk of having HBsAg marker were those who had a history of injectable medications (AOR 5.02, 95% CI: 1.14, 22.07), a family history of liver disease (AOR 6.37, 95% CI: 1.32, 30.74), a HBsAg seropositive mothers, (AOR 11.19, (95% CI: 3.15, 39.67), and had no vaccination history for HBV (AOR, 6.37, 95% CI: 1.32, 30.74). Children from families with low monthly income, who were home delivered, unvaccinated for HBV or with HBsAg seropositive mother had increased risk of having anti-HBc. CONCLUSIONS: The study findings showed an intermediate endemicity of HBV infection in the study setting. The observed rate of residual HBV infection with low rate of immunized children after HBV vaccination was high. Hence, introducing birth dose vaccine, safe injection practice and improving immunization coverage during pregnancy as part of the antenatal care package should be considered. Furthermore, governmental and non-governmental organizations should give attention on timely measures for the prevention of ongoing vertical transmission from mother to child as well as early horizontal transmission of HBV in Hawassa City, Ethiopia.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B/sangue , Hepatite B/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Biomarcadores/sangue , Criança , Pré-Escolar , Estudos Transversais , Etiópia/epidemiologia , Feminino , Hepatite B/prevenção & controle , Hepatite B/transmissão , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Humanos , Transmissão Vertical de Doença Infecciosa/prevenção & controle , Masculino , Gravidez , Complicações Infecciosas na Gravidez/sangue , Complicações Infecciosas na Gravidez/prevenção & controle , Complicações Infecciosas na Gravidez/virologia , Cuidado Pré-Natal/métodos , Prevalência , Fatores de Risco , Inquéritos e Questionários , Vacinação/métodos
13.
Lancet Glob Health ; 8(7): e931-e941, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32562649

RESUMO

BACKGROUND: Hepatitis B causes more than 800 000 deaths globally each year. Perinatal infections are a major driver of this burden but can be prevented by vaccination within 24 h of birth. Currently, only 44% of newborn babies in low-income and middle-income countries (LMICs) receive a timely birth dose. We investigated the effects and cost-effectiveness of implementing ambient storage of hepatitis B vaccines under a controlled temperature chain (CTC) protocol and the use of compact prefilled auto-disable (CPAD) devices for community births. METHODS: In this mathematical modelling study of perinatal hepatitis B transmission and disease progression, we estimated the coverage impact and cost-effectiveness of implementing CTC and CPAD interventions in the six Global Burden of Disease (GBD) regions containing LMICs. Combinations of four different scenarios of birth dose delivery strategies (cold chain, CTC) and interventions (needle and syringe, CPAD) were modelled across facility or community birth locations. We also estimated the minimum cost and most cost-effective strategy to achieve the WHO 90% hepatitis B birth dose coverage target in GBD regions and in 46 LMICs with a reported coverage of less than 90%. FINDINGS: Current delivery protocols achieved a maximum coverage of 65% (IQR 64-65) across GBD regions. Reaching 90% hepatitis B birth dose coverage across all GBD regions was estimated to cost a minimum of US$687·5 million per annum ($494·0 million more than the estimated current expenditure), of which $516·5 million (75%) was required for CTC and CPAD interventions. Reaching 90% coverage in this way was estimated to be cost saving in five of the six regions (and in 40 of 46 LMICs individually assessed) due to the disease costs averted, with the cost per disability-adjusted life-years averted being less than $83·27 otherwise. INTERPRETATION: Hepatitis B birth dose coverage of 90% is unlikely to be reached under current protocols. CTC and CPAD vaccine strategies present cost-effective solutions to overcome coverage barriers. FUNDING: The Burnet Institute.


Assuntos
Países em Desenvolvimento , Armazenamento de Medicamentos/métodos , Vacinas contra Hepatite B/administração & dosagem , Hepatite B/prevenção & controle , Cobertura Vacinal/estatística & dados numéricos , Custos e Análise de Custo , Armazenamento de Medicamentos/economia , Feminino , Objetivos , Programas Gente Saudável , Hepatite B/epidemiologia , Hepatite B/transmissão , Humanos , Recém-Nascido , Transmissão Vertical de Doença Infecciosa/prevenção & controle , Modelos Teóricos , Gravidez , Temperatura
14.
BMC Public Health ; 20(1): 920, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532228

RESUMO

BACKGROUND: hepatitis B virus (HBV) and C virus (HCV) are among the leading causes of mortality worldwide. Health care personnel (HCP) are subjected to increased risk of these infections. Therefore, HBV vaccination and post-vaccination serologic testing (PVST) are recommended for them. Our objectives in this study were investigate how well the vaccination guidelines for hospital HCPs were implemented. Moreover, the prevalence rates of HBV and HCV infections were calculated. To determine the presence of immunological memory, vaccinated personnel negative to antibody against HB surface antigen with one dose of HB vaccine were boosted. METHODS: From 1 July to 30 November 2017, a cross-sectional study among HCPs working in public hospitals were conducted. All HCPs from various professional categories potentially at risk of exposure to contaminated sources were included. The information was gathered via interview and self-administered questionnaire. The questions were focused on the demographic characteristics, HB vaccination and immunity status and time elapsed since initial vaccination series, and frequency of needelstick injuries during the past 12 months of their work. Moreover, the prevalence rate of HBV and HCV infections were calculated. To determine the presence of immunological memory, subjects negative to HBV seromarkers received a booster dose of the vaccine. RESULTS: A total of 186 out of 766 participants were male and nurses comprised 71% of personnel. Although all HCP were vaccinated, 84% of them completed the course and less than 5% of them received PVST. According to the results, 0.78, 4.6, and 83% were serologically positive to HBV surface antigen, antibodies against HBV core, and S antigens, respectively. Approximately, 91% of seronegative participants responded to a booster dose and only 0.91% of the personnel was anti-HCV positive. CONCLUSION: Most HCP received full HBV vaccination course. Although a minority did PVST, the HBV vaccine-induced long-term protection and HB vaccine booster were not required. Therefore, policies should be made to increase the rate PVST after immunization. According to the results, the HCV infection rate was low and thus pre-recruitment screening was not necessary.


Assuntos
Vacinas contra Hepatite B/administração & dosagem , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Recursos Humanos em Hospital , Adulto , Estudos Transversais , Feminino , Hepatite B/complicações , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite C/complicações , Hepatite C/prevenção & controle , Hospitais , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/epidemiologia , Doenças Profissionais/prevenção & controle , Prevalência , Inquéritos e Questionários , Vacinação/estatística & dados numéricos , Adulto Jovem
15.
J Biomed Sci ; 27(1): 70, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32466788

RESUMO

BACKGROUND: Hepatitis B virus (HBV) persistently infected about 250 million people worldwide, and a curative treatment remains an unmet medical need. Among many approaches to treat chronic hepatitis B (CHB), therapeutic vaccines have been developed for two decades, but none have yielded promising results in clinical trials. Therefore, dissection of HBV clearance mechanisms during therapeutic vaccination in appropriate models, which could give rise to new curative therapies, is urgently needed. Growing evidence indicates that prolonged and intensive exposure of antigen-specific T cells to viral antigens is a major cause of T cell exhaustion, and decreases anti-HBV immunity efficacy of therapeutic vaccination. HBV X protein (HBx) is expressed at low levels, and the understanding of its immunogenicity and potential in therapeutic CHB vaccines is limited. METHODS: HBV genome sequences from CHB patients were cloned into a pAAV plasmid backbone and transfected into immunocompetent mouse hepatocytes through hydrodynamic injection. Mice carrying > 500 IU/mL serum HBV surface antigen (HBs) for more than 4 weeks were considered HBV carriers mimicking human CHB and received 3 doses of weekly HBx vaccine by subcutaneous immunization. Serum HBV clearance was evaluated by monitoring serum HBs and HBV-DNA titers. Residual HBV in the liver was evaluated by western blotting for HBV core antigen. The splenic antigen-specific T cell response was quantified by a 15-mer overlapping peptide-stimulated interferon-γ enzyme-linked immunospot assay. Blood and hepatic immune cells were quantified by flow cytometric analysis. RESULTS: Our HBx-based vaccine induced systemic HBx-specific CD4+ and CD8+ T cell responses in HBV carrier mice and demonstrated significant HBs and HBV-DNA elimination. The protective effect persisted for at least 30 days without additional booster immunization. Different infiltrating myeloid cell subsets, each with distinctive roles during immune-mediated HBV clearance, were found in the liver of vaccinated mice. During vaccine therapy, inflammatory monocyte depletion resulted in sustained HBV clearance inhibition, whereas phagocytic monocyte-derived macrophage and Kupffer cell elimination resulted in only transient inhibition of vaccine-induced HBV clearance. CONCLUSIONS: We report the potential role of HBx as a major immunogen in an HBV therapeutic vaccine and the significance of a liver-infiltrating monocyte subset during hepatic viral clearance.


Assuntos
Antígenos da Hepatite B/metabolismo , Vacinas contra Hepatite B/administração & dosagem , Vírus da Hepatite B/imunologia , Fígado/virologia , Monócitos/metabolismo , Transativadores/administração & dosagem , Proteínas Virais Reguladoras e Acessórias/administração & dosagem , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA
16.
PLoS One ; 15(4): e0232207, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32343712

RESUMO

BACKGROUND: Chronic hepatitis B (CHB) is endemic in the Aboriginal population of Australia's Northern Territory (NT). However, many people's hepatitis B virus (HBV) status remains unknown. OBJECTIVE: 1. To maximise the utility of existing HBV test and vaccination data in the NT by creating a linked dataset and computerised algorithmic coding. 2. To undertake rigorous quality assurance processes to establish feasibility of using the linked dataset and computerised algorithmic coding for individual care for people living with CHB. METHODS: Step 1: We used deterministic data linkage to merge information from three separate patient databases. HBV testing and vaccination data from 2008-2016 was linked and extracted for 19,314 people from 21 remote Aboriginal communities in the Top End of the NT. Step 2: A computerised algorithm was developed to allocate one of ten HBV codes to each individual. Step 3: A quality assurance process was undertaken by a clinician, using standardised processes, manually reviewing all three databases, for a subset of 5,293 Aboriginal people from five communities to check the accuracy of each allocated code. RESULTS: The process of data linking individuals was highly accurate at 99.9%. The quality assurance process detected an overall error rate of 17.7% on the HBV code generated by the computerised algorithm. Errors occurred in source documentation, primarily from the historical upload of paper-based records to electronic health records. An overall HBV prevalence of 2.6% in five communities was found, which included ten cases of CHB who were previously unaware of infection and not engaged in care. CONCLUSIONS: Data linkage of individuals was highly accurate. Data quality issues and poor sensitivity in the codes produced by the computerised algorithm were uncovered in the quality assurance process. By systematically, manually reviewing all available data we were able to allocate a HBV status to 91% of the study population.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Hepatite B Crônica/epidemiologia , Armazenamento e Recuperação da Informação , Grupo com Ancestrais Oceânicos , Algoritmos , Bases de Dados Factuais/estatística & dados numéricos , Doenças Endêmicas/prevenção & controle , Vacinas contra Hepatite B/administração & dosagem , Hepatite B Crônica/prevenção & controle , Hepatite B Crônica/terapia , Humanos , Northern Territory/epidemiologia , Garantia da Qualidade dos Cuidados de Saúde , Testes Sorológicos
17.
Medicine (Baltimore) ; 99(16): e19886, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32312015

RESUMO

BACKGROUND: This study aims at evaluating the benefits and harms of hepatitis B immune globulin (HBIG) and hepatitis B vaccine (HBVac) in preventing mother to child transmission in HBV surface antigen (HBsAg) positive pregnant women during antenatal period. METHODS: Seven electronic databases including PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), WanFang Database, Chinese Biomedical Literature Database (CBM), VIP Database for Chinese Technical Periodicals (VIP), and 3 clinical trial registry platforms were searched from inception date to December 2017. Only randomized controlled trials (RCTs) were included in this study. The Cochrane risk of bias tool was applied to assessing the risk of bias. The outcomes were analyzed by Review Manager 5.3 software. RESULTS: Sixteen RCTs involving 2440 HBsAg positive pregnant women were included in the meta-analysis. Compared with placebo group, HBIG and HBVac group had a significant decrease in the number of newborns who were HBsAg positive (relative risks [RR]: 0.2, 95% confidence interval [CI] [0.18, 0.40], P < .00001) and HBV-DNA positive (RR: 0.25, 95% CI [0.09, 0.71], P = .010), and had a significant increase in the number of anti-HBs positive newborns (RR: 3.95, 95% CI [3.11, 5.00], P < .00001). After 1-year follow up, the number of HBsAg positive newborns continued to decline (RR: 0.09, 95% CI [0.04, 0.20], P < .00001) and the number of anti-HBs positive newborns continued to increase in HBIG and HBVac group (RR: 1.30, 95% CI [1.22, 1.38], P < .00001). Compared with HBIG group, HBIG and HBVac group had no significant difference in the number of HBsAg positive newborns (RR: 1.68, 95% CI [0.66, 4.30], P = .28), and had a significant decrease in the number of HBsAg positive newborns (RR: 0.31, 95% CI [0.12, 0.84], P = .02). Additionally, only 1 study reported 2 swelling cases, 4 studies were reported no adverse events, and 11 studies were not report adverse reaction. CONCLUSIONS: HBIG and HBVac could be an effective alternative for HBsAg positive pregnant women to prevent mother to child transmission. However, due to the limitations of the study, the long-term efficacy and safety of HBIG and HBVac still need long-term and high-quality research to confirm.


Assuntos
Vacinas contra Hepatite B/administração & dosagem , Hepatite B/tratamento farmacológico , Imunoglobulinas/administração & dosagem , Transmissão Vertical de Doença Infecciosa/prevenção & controle , China/epidemiologia , DNA Viral/genética , Feminino , Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/uso terapêutico , Vírus da Hepatite B/imunologia , Humanos , Imunoglobulinas/uso terapêutico , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/virologia , Cuidado Pré-Natal/normas , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
PLoS Med ; 17(4): e1003068, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32315297

RESUMO

BACKGROUND: International Sustainable Development Goals (SDGs) for elimination of hepatitis B virus (HBV) infection set ambitious targets for 2030. In African populations, infant immunisation has been fundamental to reducing incident infections in children, but overall population prevalence of chronic hepatitis B (CHB) infection remains high. In high-prevalence populations, adult catch-up vaccination has sometimes been deployed, but an alternative Test and Treat (T&T) approach could be used as an intervention to interrupt transmission. Universal T&T has not been previously evaluated as a population intervention for HBV infection, despite high-profile data supporting its success with human immunodeficiency virus (HIV). METHODS AND FINDINGS: We set out to investigate the relationship between prevalence of HBV infection and exposure in Africa, undertaking a systematic literature review in November 2019. We identified published seroepidemiology data representing the period 1995-2019 from PubMed and Web of Science, including studies of adults that reported prevalence of both hepatitis B surface antigen (HBsAg; prevalence of HBV infection) and antibody to hepatitis B core antigen (anti-HBc; prevalence of HBV exposure). We identified 96 studies representing 39 African countries, with a median cohort size of 370 participants and a median participant age of 34 years. Using weighted linear regression analysis, we found a strong relationship between the prevalence of infection (HBsAg) and exposure (anti-HBc) (R2 = 0.45, p < 0.001). Region-specific differences were present, with estimated CHB prevalence in Northern Africa typically 30% to 40% lower (p = 0.007) than in Southern Africa for statistically similar exposure rates, demonstrating the need for intervention strategies to be tailored to individual settings. We applied a previously published mathematical model to investigate the effect of interventions in a high-prevalence setting. The most marked and sustained impact was projected with a T&T strategy, with a predicted reduction of 33% prevalence by 20 years (95% CI 30%-37%) and 62% at 50 years (95% CI 57%-68%), followed by routine neonatal vaccination and prevention of mother to child transmission (PMTCT; at 100% coverage). In contrast, the impact of catch-up vaccination in adults had a negligible and transient effect on population prevalence. The study is constrained by gaps in the published data, such that we could not model the impact of antiviral therapy based on stratification by specific clinical criteria and our model framework does not include explicit age-specific or risk-group assumptions regarding force of transmission. CONCLUSIONS: The unique data set collected in this study highlights how regional epidemiology data for HBV can provide insights into patterns of transmission, and it provides an evidence base for future quantitative research into the most effective local interventions. In combination with robust neonatal immunisation programmes, ongoing PMTCT efforts, and the vaccination of high-risk groups, diagnosing and treating HBV infection is likely to be of most impact in driving advances towards elimination targets at a population level.


Assuntos
Anticorpos Anti-Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Vírus da Hepatite B , Hepatite B/sangue , Hepatite B/epidemiologia , África/epidemiologia , Infecções por HIV/sangue , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Hepatite B/prevenção & controle , Humanos , Estudos Soroepidemiológicos , Vacinação/métodos
19.
Arq Gastroenterol ; 57(1): 69-73, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32294738

RESUMO

BACKGROUND: Patients with inflammatory bowel disease (IBD) vaccinated for hepatitis B have a low success rate in achieving protective antibody levels. The main factors suggested for this are IBD itself and the use of immunosuppressive drugs. OBJECTIVE: To evaluate the concentration of anti-HBs antibodies and to verify factors associated with the effectiveness of hepatitis B vaccination in patients with IBD. METHODS: This is a prospective, consecutive, observational, descriptive and analytical, non-randomized, qualitative study that evaluated the levels of anti-HBs antibodies in IBD patients at the Interdisciplinary Inflammatory Bowel Disease Clinic of the Family and Community Health Unit of UNIVALI - Itajaí, Santa Catarina. RESULTS: Thirty-six patients were vaccinated against hepatitis B virus (HBV), of which 29 were female. The average age was 46.2 years. Regarding the type of IBD, twenty-four patients had Crohn's disease and the duration of inflammatory bowel disease was 74 months. Fifteen patients were on concomitant immunosuppressive therapy. The effective response rate to HBV vaccine was 72.2%, verified by anti-HBs titration ≥10 UI/L. Statistical analysis revealed a negative response to vaccination in patients with Crohn's disease and immunosuppressive drugs. CONCLUSION: The success rate of HBV immunization in IBD patients is low compared to the general population. Type of disease and use of immunosuppressive drugs appear to influence the vaccine response.


Assuntos
Colite Ulcerativa/imunologia , Doença de Crohn/imunologia , Anticorpos Anti-Hepatite B/sangue , Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/diagnóstico , Hepatite B/prevenção & controle , Adulto , Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Feminino , Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/administração & dosagem , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Pesquisa Qualitativa , Soroconversão
20.
BMC Health Serv Res ; 20(1): 295, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32272920

RESUMO

BACKGROUND: The phased withdrawal of oral polio vaccine (OPV) and the introduction of inactivated poliovirus vaccine (IPV) is central to the polio 'end-game' strategy. METHODS: We analyzed the cost implications in Chile of a switch from the vaccination scheme consisting of a pentavalent vaccine with whole-cell pertussis component (wP) plus IPV/OPV vaccines to a scheme with a hexavalent vaccine with acellular pertussis component (aP) and IPV (Hexaxim®) from a societal perspective. Cost data were collected from a variety of sources including national estimates and previous vaccine studies. All costs were expressed in 2017 prices (US$ 1.00 = $Ch 666.26). RESULTS: The overall costs associated with the vaccination scheme (4 doses of pentavalent vaccine plus 1 dose IPV and 3 doses OPV) from a societal perspective was estimated to be US$ 12.70 million, of which US$ 8.84 million were associated with the management of adverse events related to wP. In comparison, the cost associated with the 4-dose scheme with a hexavalent vaccine (based upon the PAHO reference price) was US$ 19.76 million. The cost of switching to the hexavalent vaccine would be an additional US$ 6.45 million. Overall, depending on the scenario, the costs of switching to the hexavalent scheme would range from an additional US$ 2.62 million to US$ 6.45 million compared with the current vaccination scheme. CONCLUSIONS: The switch to the hexavalent vaccine schedule in Chile would lead to additional acquisition costs, which would be partially offset by improved logistics, and a reduction in adverse events associated with the current vaccines.


Assuntos
Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Vacina contra Difteria, Tétano e Coqueluche/economia , Substituição de Medicamentos/economia , Vacinas Anti-Haemophilus/administração & dosagem , Vacinas Anti-Haemophilus/economia , Vacinas contra Hepatite B/administração & dosagem , Vacinas contra Hepatite B/economia , Poliomielite/prevenção & controle , Vacina Antipólio de Vírus Inativado/administração & dosagem , Vacina Antipólio de Vírus Inativado/economia , Vacina Antipólio Oral/administração & dosagem , Vacina Antipólio Oral/economia , Vacinação/economia , Chile , Custos e Análise de Custo , Humanos , Esquemas de Imunização , Lactente , Vacinas Combinadas/administração & dosagem , Vacinas Combinadas/economia
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