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1.
Rev Soc Bras Med Trop ; 53: e20190511, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32578703

RESUMO

INTRODUCTION: The Amazon tropical rainforest has the most dense and diverse ecosystem worldwide. A few studies have addressed rodent-borne diseases as potential hazards to humans in this region. METHODS: A retrospective survey was conducted using enzyme-linked immunosorbent assay for detecting mammarenavirus and orthohantavirus antibodies in 206 samples collected from rural settlers of the Brazilian Western Amazonian region. RESULTS: Six (2.91%) individuals in the age group of 16 to 36 years were found to possess antibodies against mammarenavirus. CONCLUSION: Evidence of previous exposure to mammarenavirus in the rural population points to its silent circulation in this region.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Arenaviridae/epidemiologia , Arenaviridae/imunologia , Reservatórios de Doenças/veterinária , Hepatite Viral Humana/epidemiologia , Orthohepadnavirus/imunologia , Roedores/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Arenaviridae/classificação , Infecções por Arenaviridae/diagnóstico , Infecções por Arenaviridae/transmissão , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Hepatite Viral Humana/diagnóstico , Hepatite Viral Humana/transmissão , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Orthohepadnavirus/classificação , Estudos Retrospectivos , Roedores/classificação , População Rural , Fatores Socioeconômicos , Adulto Jovem
2.
Int J Infect Dis ; 90: 145-150, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31672659

RESUMO

INTRODUCTION: Orthohantaviruses are still a significant public health threat in endemic countries, with high case fatality rates (CFR). In Bolivia, the reporting of small outbreaks occurred until 2012. The findings of 40 laboratory-confirmed cases diagnosed in two departments are reported herein. METHODS: This was an observational, retrospective and cross-sectional study. Data on laboratory-confirmed cases in 2018 were collected from the hospitals and departmental health services (SEDES) of Santa Cruz and Tarija. An ELISA was used for the detection of IgM antibody to hantavirus in the patient blood samples. RESULTS: Forty patients were IgM-positive. The median age of the patients was 24 years (interquartile range 19-41 years) and 72.5% were male. All patients were hospitalized; 57.5% were admitted to the intensive care unit and had cardiopulmonary compromise, with 83% of these presenting acute respiratory distress syndrome and 89.5% of these requiring mechanical ventilation. Six patients died (CFR 15%). Patients <15 or >60 years old were more prone to die (odds ratio 10.33, 95% confidence interval 1.411-75.694), as were those with comorbidities (odds ratio 16.5, 95% confidence interval 1.207-225.540). CONCLUSIONS: Orthohantavirus infections were associated with a high CFR. These cases occurred in areas with eco-epidemiological conditions facilitating viral transmission, including the presence of rodents, as well as the risk of spillover to humans due to social, environmental, and occupational factors.


Assuntos
Infecções por Hepadnaviridae/virologia , Orthohepadnavirus/isolamento & purificação , Adolescente , Adulto , Idoso , Bolívia/epidemiologia , Criança , Estudos Transversais , Surtos de Doenças , Feminino , Infecções por Hepadnaviridae/diagnóstico , Infecções por Hepadnaviridae/epidemiologia , Infecções por Hepadnaviridae/mortalidade , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Orthohepadnavirus/classificação , Orthohepadnavirus/genética , Estudos Retrospectivos , Adulto Jovem
3.
Viruses ; 11(3)2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30893858

RESUMO

New technologies enable viral discovery in a diversity of hosts, providing insights into viral evolution. We used one such approach, the virome capture sequencing for vertebrate viruses (VirCapSeq-VERT) platform, on 21 samples originating from six dead Maxwell's duikers (Philantomba maxwellii) from Taï National Park, Côte d'Ivoire. We detected the presence of an orthohepadnavirus in one animal and characterized its 3128 bp genome. The highest viral copy numbers were detected in the spleen, followed by the lung, blood, and liver, with the lowest copy numbers in the kidney and heart; the virus was not detected in the jejunum. Viral copy numbers in the blood were in the range known from humans with active chronic infections leading to liver histolytic damage, suggesting this virus could be pathogenic in duikers, though many orthohepadnaviruses appear to be apathogenic in other hosts, precluding a formal test of this hypothesis. The virus was not detected in 29 other dead duiker samples from the Côte d'Ivoire and Central African Republic, suggesting either a spillover event or a low prevalence in these populations. Phylogenetic analysis placed the virus as a divergent member of the mammalian clade of orthohepadnaviruses, though its relationship to other orthohepadnaviruses remains uncertain. This represents the first orthohepadnavirus described in an artiodactyl. We have tentatively named this new member of the genus Orthohepadnavirus (family Hepadnaviridae), Taï Forest hepadnavirus. Further studies are needed to determine whether it, or some close relatives, are present in a broader range of artiodactyls, including livestock.


Assuntos
Antílopes/virologia , Orthohepadnavirus/classificação , Orthohepadnavirus/isolamento & purificação , Animais , Costa do Marfim , Variação Genética , Genoma Viral , Parques Recreativos , Filogenia
4.
Virology ; 531: 162-170, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30884426

RESUMO

Limited sampling means that relatively little is known about the diversity and evolutionary history of mammalian members of the Hepadnaviridae (genus Orthohepadnavirus). An important case in point are shrews, the fourth largest group of mammals, but for which there is limited knowledge on the role they play in viral evolution and emergence. Here, we report the discovery of a novel shrew hepadnavirus. The newly discovered virus, denoted shrew hepatitis B virus (SHBV), is divergent to be considered a new species of Orthohepadnavirus. Phylogenetic analysis revealed that these viruses were usually most closely related to TBHBV (tent-making bat hepatitis B virus), known to be able to infect human hepatocytes, and had a similar genome structure, although SHBV fell in a more basal position in the surface protein phylogeny. In sum, these data suggest that shrews are natural hosts for hepadnaviruses and may have played an important role in their long-term evolution.


Assuntos
Evolução Molecular , Infecções por Hepadnaviridae/veterinária , Infecções por Hepadnaviridae/virologia , Hepadnaviridae/isolamento & purificação , Musaranhos/virologia , Sequência de Aminoácidos , Animais , China , Genoma Viral , Hepadnaviridae/química , Hepadnaviridae/classificação , Hepadnaviridae/genética , Infecções por Hepadnaviridae/transmissão , Hepatócitos/virologia , Humanos , Orthohepadnavirus/classificação , Orthohepadnavirus/genética , Orthohepadnavirus/isolamento & purificação , Filogenia , Alinhamento de Sequência , Musaranhos/classificação , Proteínas Virais/química , Proteínas Virais/genética
5.
Arch Virol ; 163(12): 3291-3301, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30191374

RESUMO

Hantavirus cardiopulmonary syndrome (HPS) has gained importance in Latin America as an emerging disease, with reports of about 4000 HPS cases; however, this is probably an underestimate because of limited surveillance programs and diagnostic tools to confirm HPS. In order to address this issue and develop better serosurveillance capability, we evaluated three recombinant peptides from the Necoclí virus (NECV) nucleocapsid in antibody-capture ELISA. We cloned and expressed antigens representing the whole NECV nucleocapsid protein (NECV-rN), the immunodominant domain (NECV-rN100), and a serospecific domain (NECV-rN428), and then we compared these antigens in ELISA to detect IgG antibodies to NECV in human sera. We evaluated human sera collected during two epidemiological studies from the area where NECV was discovered. The first group included 609 sera from healthy individuals, and the second one included 89 samples from patients with undifferentiated febrile illness. In these two groups, hantavirus infection had previously been determined by the presence of IgG to Maciel virus (MCLV), a hantavirus closely related to NECV. The number of IgG-positive sera was higher using the Necoclí ELISA with the rN100 protein, which detected antibodies in a higher percentage of healthy individuals, 129/609 (21.2%), as well as in febrile patients, 11/89 (12.3%). In contrast, using MCLV ELISA, 8 of 609 (1.3%) and 4 of 89 (4.5%) samples from healthy and febrile patients, respectively, were seropositive. The agreement between the NECV and MCLV ELISA assays was ≥ 82.3%; however, the kappa indices were weak but statistically significant for rN (0.251 CI; 0.138-0.365) and rN100rN (0.153 CI; 0.084-0.223). The weak kappa indices were attributed to decreased MCLV ELISA assay sensitivity. These results suggest that NECV rN and rN100 have increased specificity and could be further validated for improved diagnosis of hantavirus infections.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Infecções por Hepadnaviridae/diagnóstico , Orthohepadnavirus/isolamento & purificação , Adolescente , Animais , Anticorpos Antivirais/sangue , Criança , Feminino , Infecções por Hepadnaviridae/sangue , Infecções por Hepadnaviridae/virologia , Humanos , Imunoglobulina G/sangue , Masculino , Proteínas do Nucleocapsídeo/imunologia , Orthohepadnavirus/classificação , Orthohepadnavirus/genética , Orthohepadnavirus/imunologia , Estudos Retrospectivos , Roedores/sangue , Roedores/virologia , Sensibilidade e Especificidade
6.
Ecohealth ; 15(3): 577-589, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30105563

RESUMO

New World orthohantaviruses are emerging RNA viruses that cause hantavirus cardiopulmonary syndrome (HCPS). These viruses are a burden to public health around the world with a lethality rate of around 60%. In South America, rodents of Sigmodontinae subfamily are the main reservoirs of orthohantaviruses. We described a serosurvey for orthohantaviruses circulation in an apparently healthy human population and small mammals from rural areas in Central Minas Gerais State, Brazil. A total of 240 individuals and 50 small mammals (26 rodents belonging to 10 different species and 24 marsupials from 4 different species) were sampled during 2012-2013. The seroprevalence rates of IgG/IgM antibodies in humans were 7.1 and 1.6%, respectively. Only one rodent, an Oligoryzomys nigripes captured in peridomestic area, tested positive for IgG antibodies and viral RNA. Our findings suggest a silent circulation of orthohantaviruses in a region of intensive agriculture production. The detection of seropositive humans in an area with a lack of previous HCPS reports highlights potential oligosymptomatic cases and the need for surveillance strategies that could reduce the risk of future outbreaks.


Assuntos
Reservatórios de Doenças/virologia , Infecções por Hantavirus/transmissão , Mamíferos/virologia , Orthohepadnavirus/isolamento & purificação , Roedores/virologia , Animais , Brasil/epidemiologia , Infecções por Hantavirus/epidemiologia , Humanos , Estudos Soroepidemiológicos
7.
Infect Genet Evol ; 63: 135-143, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29842981

RESUMO

The orthohepadnaviruses, which include the major human pathogen hepatitis B virus, exist in a wide range of hosts. Since 2013, a large group of orthohepadnaviruses has been identified in bats worldwide and classified as 4 species within the genus Orthohepadnavirus. To further investigate orthohepadnaviruses in the Chinese bat population, 554 archived bat samples from 20 colonies covering 3 southern provinces were screened with results showing that 9 (1.6%) were positive. A systematic phylogenetic analysis has indicated the need for a new nomenclature for bat hepatitis B virus-like viruses: BtHBV, with the addition of 3 new species, one being divided into 6 genotypes. Viruses identified here shared 9.0-19.2% full genome divergence and classified into 3 different genotypes. This study illustrates the genetic diversity of orthohepadnaviruses in the Chinese bat population, and emphasizes need for further investigation of their public health significance.


Assuntos
Quirópteros/virologia , Variação Genética , Infecções por Hepadnaviridae/veterinária , Hepatite Viral Animal/virologia , Orthohepadnavirus/classificação , Orthohepadnavirus/genética , Animais , China , Genoma Viral , Infecções por Hepadnaviridae/epidemiologia , Infecções por Hepadnaviridae/virologia , Hepatite Viral Animal/epidemiologia , Filogenia
8.
J Hepatol ; 68(6): 1114-1122, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29428874

RESUMO

BACKGROUND & AIMS: All known hepatitis B virus (HBV) genotypes occur in humans and hominoid Old World non-human primates (NHPs). The divergent woolly monkey HBV (WMHBV) forms another orthohepadnavirus species. The evolutionary origins of HBV are unclear. METHODS: We analysed sera from 124 Brazilian monkeys collected during 2012-2016 for hepadnaviruses using molecular and serological tools, and conducted evolutionary analyses. RESULTS: We identified a novel orthohepadnavirus species in capuchin monkeys (capuchin monkey hepatitis B virus [CMHBV]). We found CMHBV-specific antibodies in five animals and high CMHBV concentrations in one animal. Non-inflammatory, probably chronic infection was consistent with an intact preCore domain, low genetic variability, core deletions in deep sequencing, and no elevated liver enzymes. Cross-reactivity of antisera against surface antigens suggested antigenic relatedness of HBV, CMHBV, and WMHBV. Infection-determining CMHBV surface peptides bound to the human HBV receptor (human sodium taurocholate co-transporting polypeptide), but preferentially interacted with the capuchin monkey receptor homologue. CMHBV and WMHBV pseudotypes infected human hepatoma cells via the human sodium taurocholate co-transporting polypeptide, and were poorly neutralised by HBV vaccine-derived antibodies, suggesting that cross-species infections may be possible. Ancestral state reconstructions and sequence distance comparisons associated HBV with humans, whereas primate hepadnaviruses as a whole were projected to NHP ancestors. Co-phylogenetic analyses yielded evidence for co-speciation of hepadnaviruses and New World NHP. Bayesian hypothesis testing yielded strong support for an association of the HBV stem lineage with hominoid ancestors. Neither CMHBV nor WMHBV was likely the ancestor of the divergent human HBV genotypes F/H found in American natives. CONCLUSIONS: Our data suggest ancestral co-speciation of hepadnaviruses and NHP, and an Old World origin of the divergent HBV genotypes F/H. The identification of a novel primate hepadnavirus offers new perspectives for urgently needed animal models of chronic hepatitis B. LAY SUMMARY: The origins of HBV are unclear. The new orthohepadnavirus species from Brazilian capuchin monkeys resembled HBV in elicited infection patterns and could infect human liver cells using the same receptor as HBV. Evolutionary analyses suggested that primate HBV-related viruses might have emerged in African ancestors of New World monkeys millions of years ago. HBV was associated with hominoid primates, including humans and apes, suggesting evolutionary origins of HBV before the formation of modern humans. HBV genotypes found in American natives were divergent from those found in American monkeys, and likely introduced along prehistoric human migration. Our results elucidate the evolutionary origins and dispersal of primate HBV, identify a new orthohepadnavirus reservoir, and enable new perspectives for animal models of hepatitis B.


Assuntos
Cebus/virologia , Evolução Molecular , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Orthohepadnavirus/genética , Orthohepadnavirus/isolamento & purificação , Sequência de Aminoácidos , Animais , Teorema de Bayes , Brasil , Especiação Genética , Genoma Viral , Hepatite B/veterinária , Hepatite B/virologia , Antígenos da Hepatite B/química , Antígenos da Hepatite B/genética , Antígenos da Hepatite B/imunologia , Vírus da Hepatite B/classificação , Interações entre Hospedeiro e Microrganismos/genética , Humanos , Modelos Genéticos , Doenças dos Macacos/virologia , Transportadores de Ânions Orgânicos Dependentes de Sódio/fisiologia , Orthohepadnavirus/classificação , Filogenia , Primatas/virologia , Receptores Virais/fisiologia , Simportadores/fisiologia , Internalização do Vírus
9.
Artigo em Inglês | MEDLINE | ID: mdl-25833941

RESUMO

Australian antigen, the envelope protein of hepatitis B virus (HBV), was discovered in 1967 as a prevalent serum antigen in hepatitis B patients. Early electron microscopy (EM) studies showed that this antigen was present in 22-nm particles in patient sera, which were believed to be incomplete virus. Complete virus, much less abundant than the 22-nm particles, was finally visualized in 1970. HBV was soon found to infect chimpanzees, gorillas, orangutans, gibbon apes, and, more recently, tree shrews (Tupaia belangeri) and cynomolgus macaques (Macaca fascicularis). This restricted host range placed limits on the kinds of studies that might be performed to better understand the biology and molecular biology of HBV and to develop antiviral therapies to treat chronic infections. About 10 years after the discovery of HBV, this problem was bypassed with the discovery of viruses related to HBV in woodchucks, ground squirrels, and ducks. Although unlikely animal models, their use revealed the key steps in hepadnavirus replication and in the host response to infection, including the fact that the viral nuclear episome is the ultimate target for immune clearance of transient infections and antiviral therapy of chronic infections. Studies with these and other animal models have also suggested interesting clues into the link between chronic HBV infection and hepatocellular carcinoma.


Assuntos
Modelos Animais de Doenças , Infecções por Hepadnaviridae/virologia , Hepadnaviridae/genética , Animais , DNA Viral/biossíntese , Genoma Viral , Hepadnaviridae/classificação , Hepadnaviridae/fisiologia , Vírus da Hepatite B do Pato , Hepatite B Crônica/virologia , Humanos , Neoplasias Hepáticas/virologia , Orthohepadnavirus
10.
Arch Virol ; 160(1): 335-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25193071

RESUMO

Bats in Myanmar, Gabon, and Panama have been found to harbor diverse hepadnaviruses. Here, we report a novel hepadnavirus in 4 of 20 pomona roundleaf bats from Yunnan province, China. This virus contains 3,278 nucleotides (nt) in the full circularized genome, with four predicted open frames (ORFs) reading in the same direction. Full genomic sequence comparisons and evolutionary analysis indicate that this virus is a member of a new species within the genus Orthohepadnavirus.


Assuntos
Quirópteros , Infecções por Hepadnaviridae/veterinária , Hepatite Viral Animal/virologia , Orthohepadnavirus/isolamento & purificação , Animais , Evolução Biológica , China/epidemiologia , Variação Genética , Infecções por Hepadnaviridae/epidemiologia , Infecções por Hepadnaviridae/virologia , Hepatite Viral Animal/epidemiologia , Orthohepadnavirus/genética , Filogenia
11.
Clin Mol Hepatol ; 20(3): 228-36, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25320725

RESUMO

Prediction of liver fibrosis progression has a key role in the management of chronic viral hepatitis, as it will be translated into the future risk of cirrhosis and its various complications including hepatocellular carcinoma. Both hepatitis B and C viruses mainly lead to fibrogenesis induced by chronic inflammation and a continuous wound healing response. At the same time direct and indirect profibrogenic responses are also elicited by the viral infection. There are a handful of well-established risk factors for fibrosis progression including older age, male gender, alcohol use, high viral load and co-infection with other viruses. Metabolic syndrome is an evolving risk factor of fibrosis progression. The new notion of regression of advanced fibrosis or even cirrhosis is now strongly supported various clinical studies. Even liver biopsy retains its important role in the assessment of fibrosis progression, various non-invasive assessments have been adopted widely because of their non-invasiveness, which facilitates serial applications in large cohorts of subjects. Transient elastography is one of the most validated tools which has both diagnostic and prognostic role. As there is no single perfect test for liver fibrosis assessment, algorithms combining the most validated noninvasive methods should be considered as initial screening tools.


Assuntos
Hepatite Crônica/patologia , Hepatite Viral Humana/patologia , Cirrose Hepática/patologia , Fatores Etários , Antivirais/uso terapêutico , Biomarcadores/sangue , Hepatite Crônica/tratamento farmacológico , Hepatite Viral Humana/tratamento farmacológico , Humanos , Fígado/diagnóstico por imagem , Orthohepadnavirus/genética , Fatores de Risco , Ultrassonografia
12.
Emerg Infect Dis ; 19(4): 638-40, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23631923

RESUMO

During an analysis of the virome of bats from Myanmar, a large number of reads were annotated to orthohepadnaviruses. We present the full genome sequence and a morphological analysis of an orthohepadnavirus circulating in bats. This virus is substantially different from currently known members of the genus Orthohepadnavirus and represents a new species.


Assuntos
Quirópteros/virologia , Genoma Viral , Hepatite Viral Animal/epidemiologia , Orthohepadnavirus/genética , RNA Viral/genética , Animais , Hepatite Viral Animal/virologia , Mianmar/epidemiologia , Orthohepadnavirus/classificação , Orthohepadnavirus/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase , Prevalência , RNA Viral/classificação , RNA Viral/isolamento & purificação , Análise de Sequência de DNA
13.
PLoS One ; 6(8): e23392, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21850270

RESUMO

Orthohepadnavirus (mammalian hosts) and avihepadnavirus (avian hosts) constitute the family of Hepadnaviridae and differ by their capability and inability for expression of protein X, respectively. Origin and functions of X are unclear. The evolutionary analysis at issue of X indicates that present strains of orthohepadnavirus started to diverge about 25,000 years ago, simultaneously with the onset of avihepadnavirus diversification. These evolutionary events were preceded by a much longer period during which orthohepadnavirus developed a functional protein X while avihepadnavirus evolved without X. An in silico generated 3D-model of orthohepadnaviral X protein displayed considerable similarity to the tertiary structure of DNA glycosylases (key enzymes of base excision DNA repair pathways). Similarity is confined to the central domain of MUG proteins with the typical DNA-binding facilities but without the capability of DNA glycosylase enzymatic activity. The hypothetical translation product of a vestigial X reading frame in the genome of duck hepadnavirus could also been folded into a DNA glycosylase-like 3D-structure. In conclusion, the most recent common ancestor of ortho- and avihepadnavirus carried an X sequence with orthology to the central domain of DNA glycosylase.


Assuntos
DNA Glicosilases/química , DNA Glicosilases/metabolismo , Transativadores/química , Transativadores/metabolismo , Animais , Avihepadnavirus/enzimologia , DNA Glicosilases/genética , Humanos , Orthohepadnavirus/enzimologia , Estrutura Secundária de Proteína , Transativadores/genética
14.
Expert Rev Anti Infect Ther ; 9(6): 685-700, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21692673

RESUMO

Management of viral infections after transplantation involves antiviral drug therapy (if available) and reduction in immunosuppression, which allows for development of pathogen-specific immunity to the offending virus. Prevention of viral infections is of the utmost importance, and this may be accomplished through vaccination, antiviral strategies and infection control measures. This article discusses the current management of selected viral pathogens that cause clinical illness in solid organ transplant recipients. The benefits and toxicities of antiviral therapies are discussed in the context of prevention and treatment of various viral diseases. The emerging issue of antiviral resistance is emphasized for cytomegalovirus, recurrent hepatitis B and influenza, while the importance of immunominimization is discussed in the management of BK nephropathy and virus-associated malignancies.


Assuntos
Antivirais/uso terapêutico , Infecções por Citomegalovirus/terapia , Hepatite Viral Humana/terapia , Infecções por Herpesviridae/terapia , Imunossupressão/efeitos adversos , Influenza Humana/terapia , Transplante de Órgãos/efeitos adversos , Infecções por Polyomavirus/terapia , Transplantes , Vírus BK/crescimento & desenvolvimento , Ensaios Clínicos como Assunto , Citomegalovirus/crescimento & desenvolvimento , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Hepatite Viral Humana/imunologia , Hepatite Viral Humana/virologia , Herpesviridae/crescimento & desenvolvimento , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Humanos , Imunização/métodos , Hospedeiro Imunocomprometido , Influenza Humana/imunologia , Influenza Humana/virologia , Orthohepadnavirus/crescimento & desenvolvimento , Orthomyxoviridae/crescimento & desenvolvimento , Infecções por Polyomavirus/imunologia , Infecções por Polyomavirus/virologia
15.
J Infect Dev Ctries ; 4(10): 616-20, 2010 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-21045353

RESUMO

INTRODUCTION: The study aimed to determine hepatitis B vaccination status and assess the exposure of risk factors for hepatitis B and C among primary schoolteachers in Karachi, Pakistan. METHODOLOGY: In two hundred school teachers from 30 primary schools in Karachi participated in the study between January and June 2008 by completing an anonymous, self-administered questionnaire. Exposure to and knowledge of hepatitis B and C were assessed, as well as mode of transmission and prevention. The percentage of vaccinated and non-vaccinated teachers was also estimated. RESULTS: Only 73 (36.5%) respondents were vaccinated against HBV. Nine percent (17) of the teachers had received more than 10 therapeutic injections while about 56% (101) took between 5-10 injections per annum. Fifteen (8%) of the teachers confirmed they had been injected with re-used syringes. More than 8% (17) of participants' family members were suffering from hepatitis B or C, while 10% (20) of family members had died of liver diseases without any known history. More than 13% (27) of participants shared razors, brushes, cigarettes and hukahs. Statistically significant difference was also observed in risk factors of hepatitis B and C among male and female respondents. CONCLUSION: Hepatitis B vaccination among school teachers of Karachi was around 37% with a high use of therapeutic injections and syringe reuse. Health awareness programs and educational workshops are needed for teachers, who can later educate the children.


Assuntos
Docentes , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Instituições Acadêmicas , Adulto , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Hepatite B/prevenção & controle , Hepatite B/transmissão , Vacinas contra Hepatite B/administração & dosagem , Hepatite C/prevenção & controle , Hepatite C/transmissão , Humanos , Masculino , Pessoa de Meia-Idade , Orthohepadnavirus , Paquistão/epidemiologia , Fatores de Risco , Inquéritos e Questionários , Vacinação/estatística & dados numéricos
16.
Indian J Pathol Microbiol ; 53(2): 308-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20551540

RESUMO

Blood transfusion is an important mode of transmission of infections to recipients. The aim of the study was to assess the prevalence of transfusion-transmissible infections among blood donors. For this, a 3.5-year retrospective study, from October 2002 to April 2006 was conducted at the blood transfusion centre of Maharaja Agrasen Medical College, Agroha (Hisar) Haryana. Donors were screened for seroprevalence of HIV, HBV, HCV and syphilis. A total of 5849 donors were tested, out of which 4010 (68.6%) were replacement donors and 1839 (31.4%) were voluntary donors. The seroprevalence of HIV was 0.3% in the donors. No voluntary donor was found to be positive for HIV. The low sero-positivity among donors is attributed to pre-donation counseling in donor selection. The seroprevalence of HBV, HCV and syphilis was 1.7%, 1.0% and 0.9% respectively in total donors. The seroprevalence of hepatitis and syphilis was more in replacement donors as compared to voluntary donors.


Assuntos
Doadores de Sangue , Infecções por HIV/epidemiologia , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Sífilis/epidemiologia , Adolescente , Adulto , Fatores Etários , Feminino , Soroprevalência de HIV , Hepacivirus , Humanos , Índia/epidemiologia , Masculino , Orthohepadnavirus , Estudos Soroepidemiológicos , Fatores Sexuais , Adulto Jovem
17.
Virol J ; 7: 60, 2010 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-20233455

RESUMO

BACKGROUND: The objective of this study is to established evidence of the existence of a novel member of the hepadnavirus family endemic in swine. Temporarily this virus was designated as swine hepatitis B virus (SHBV). This SHBV can be detected by using human hepatitis B virus diagnostic kits including ELISA, immunohistochemical staining, and transmission electron microscopy (TEM). Also seroprevalence of pig farms in Beijing, China, and pathological features of SHBV infection was determined. RESULTS: Screened result shows that overall prevalence of HBsAg was 24.8%, closed to that of anti-HBsAg, whereas HBeAg and anti-HBe were barely detectable. The distribution of HBsAg and HBcAg was examined by immunohistochemistry of liver samples. Typical hepatitis pathological change, such as spotty parenchymal cell degeneration, necrosis of hepatocytes and proliferation of fibrous connective tissue were observed during histopathological analysis. Analysis of HBsAg-positive serum with TEM revealed two morphologic forms, 20 nm and 40 nm sized particles, similar to small spherical and Danes particles of HBV. Observation of the ultrastructure of the liver also found HBV-like particles in the nucleus of hepatocytes. CONCLUSION: Our research result implies that SHBV could be a causative agent of swine. The discovery of SHBV will unveil novel evolutionary aspects of hepatitis and provides new information for further hepadnavirus research.


Assuntos
Infecções por Hepadnaviridae/epidemiologia , Hepatite Viral Animal/epidemiologia , Orthohepadnavirus/classificação , Orthohepadnavirus/imunologia , Doenças dos Suínos/epidemiologia , Animais , China/epidemiologia , Doenças Endêmicas , Ensaio de Imunoadsorção Enzimática , Infecções por Hepadnaviridae/virologia , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite Viral Animal/virologia , Histocitoquímica , Humanos , Imuno-Histoquímica , Fígado/patologia , Fígado/virologia , Microscopia , Microscopia Eletrônica de Transmissão , Orthohepadnavirus/isolamento & purificação , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/virologia , Vírion/ultraestrutura
18.
J Med Virol ; 82(1): 104-15, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19950245

RESUMO

The hepatitis B e-antigen (HBeAg) is a non-particulate secretory protein expressed by all viruses within the family Hepadnaviridae. It is not essential for viral assembly or replication but is important for establishment of persistent infection in vivo. Although the exact mechanism(s) by which the HBeAg manifests chronicity are unclear, the HBeAg elicits both humoral and cell-mediated immunity, down-regulates the innate immune response to infection, as well as functioning as a T cell tolerogen and regulating the immune response to the intracellular nucleocapsid. A bioinformatics approach was used to show that the HBeAg and precursory genetic codes share remarkable sequence conservation in all mammalian-infecting hepadnaviruses, irrespective of host, genotype, or geographic origin. Whilst much of this sequence conservation was within key immunomodulatory epitopes, highest conservation was observed at the unique HBeAg N-terminus, suggesting this sequence in particular may play an important role in HBeAg function.


Assuntos
Sequência de Aminoácidos , Sequência Conservada , Hepadnaviridae/imunologia , Antígenos E da Hepatite B/genética , Orthohepadnavirus , Precursores de Proteínas , Animais , Sequência de Bases , Biologia Computacional , Genótipo , Hepadnaviridae/genética , Antígenos E da Hepatite B/química , Antígenos E da Hepatite B/metabolismo , Dados de Sequência Molecular , Mutação , Orthohepadnavirus/genética , Orthohepadnavirus/imunologia , Precursores de Proteínas/química , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Alinhamento de Sequência
19.
J Med Virol ; 81(10): 1734-42, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19697413

RESUMO

Sporadic cases of acute hepatitis E virus (HEV) infection with production of anti-HEV IgM have been reported occasionally in Taiwan despite no reported outbreaks in the past. This study was undertaken to determine whether serological markers correlated with virus detection. From 2002 to 2006, 72 reported cases of acute hepatitis E seropositive for anti-HEV IgM in Taiwan were enrolled for investigation. Acute phase serum samples were collected for detection of HEV RNA, HBV DNA, HCV RNA, and GBV-C RNA by PCR. The results showed that viral sequences of HEV, HBV, HCV and GBV-C were detected in 54 (75%), 21 (29.2%), 9 (12.5%), and 22 (30.6%) of cases, respectively. Acute hepatitis A co-infection was excluded in all patients because none were seropositive for anti-HAV IgM and, nine patients (12.5%) did not seroconvert to anti-HEV IgG. These results suggest that serum markers did not correlate completely with viremia in the diagnosis of acute HEV infection. Multiple viruses may co-infect with acute hepatitis E virus in Taiwan. Detection of hepatitis E viremia together with seropositivity for anti-HEV IgM and followed by seroconversion to anti-HEV IgG should be included in the diagnostic criteria for HEV infection.


Assuntos
Comorbidade , Vírus da Hepatite E/isolamento & purificação , Hepatite E/epidemiologia , Reação em Cadeia da Polimerase/métodos , Adulto , Idoso , Feminino , Vírus GB C/isolamento & purificação , Hepacivirus/isolamento & purificação , Anticorpos Anti-Hepatite/sangue , Hepatite E/virologia , Vírus da Hepatite E/genética , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Orthohepadnavirus/isolamento & purificação , Soro/virologia , Taiwan/epidemiologia , Viremia , Adulto Jovem
20.
Vaccine ; 27(41): 5692-9, 2009 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-19615480

RESUMO

To prepare a human HBV vaccine, investigators need an animal model that can help them screen and prioritize vaccine candidates. In this study, HBV/HLA-A2.1 double transgenic mice (dTg), confirmed by analysis of genomic integration and by observation of long-term expression of HBV and HLA genes, were generated for the first time. The HBV/HLA-A2.1 dTg not only display tolerance to HBV antigens (Ags), but also have the ability to process and present HLA-A2 restricted antigenic epitopes. The animals vaccinated with HLA-A2 restricted HBc(18-27) or HBs(183-191) epitope peptide vaccine induced effective HLA-A2 restricted peptide-specific cytolytic T lymphocyte responses. This was supported by the evidence of cytotoxicity assay, ELISPOT and tetramer staining analysis. Furthermore, T cell tolerance against HBV Ags in HBV/HLA-A2.1 dTg was broken by the HBc(18-27) or HBs(183-191) peptide vaccine. In conclusion, HBV/HLA-A2.1 dTg was demonstrated to be useful model for in vivo immunogenicity testing of human HBV-based vaccines.


Assuntos
Vacinas contra Hepatite B/imunologia , Modelos Animais , Orthohepadnavirus/imunologia , Animais , Testes Imunológicos de Citotoxicidade , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Antígeno HLA-A2/genética , Humanos , Camundongos , Camundongos Transgênicos , Orthohepadnavirus/genética , Linfócitos T Citotóxicos/imunologia , Vacinas de Subunidades/imunologia
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