Hepatitis A and E among immigrants and refugees in Central Brazil

ABSTRACT OBJECTIVE To estimate the prevalence of hepatitis A virus (HAV) and hepatitis E virus (HEV) among immigrants and refugees in Goiás, Central Brazil. METHODS Overall, 355 individuals were interviewed, and blood samples were tested for anti-HAV and anti-HEV IgG. Anti-HEV-positive samples were similarly tested for HEV RNA. RESULTS All participants were from Latin American countries, most of whom, young adult males. The overall anti-HAV IgG prevalence was 87.4% (95%CI: 83.5-90.4), of whom 94.9%, 75.6%, and 60% were from Haiti, Venezuela, and other Latin American countries, respectively (p < 0.001). Age above 19 years and more than 36 months residing in Brazil were associated with a higher prevalence of previous HAV and HEV infection, respectively. Of the children eligible for HAV vaccination according to the National Immunization Program, only eight (44%) had been vaccinated. The overall anti-HEV IgG prevalence was 6.5% (95%CI: 4.4-9.5). All anti-HEV IgG-positive individuals were Haitians, including a child born in Brazil. HEV RNA was detected in two of the anti-HEV IgG-positive samples. CONCLUSION The survey detected a high prevalence of anti-HAV and anti-HEV IgG among immigrants and refugees, and active HEV infection among some Haitian participants. Prevention measures are urgently required to interrupt enteric virus transmission in this emergent and vulnerable population.

Incidence of hepatitis A and hepatitis E viruses and norovirus and rotavirus in fish and shrimp samples caught from the Persian Gulf / [Incidência de vírus da hepatite A e hepatite E e norovírus e rotavírus em amostras de peixes e camarões capturados no Golfo Pérsico]

Foodborne viruses including hepatitis A virus (HAV), norovirus (NoV), rotavirus (RoV) and hepatitis E virus (HEV) are easily transmitted through contaminated seafoods. The current research was done to assess the incidence of RoV, NoV GI and GII,hAV and hEV in fish and shrimp samples caught from the Persian Gulf, Iran. Three-hundred and twenty fish and shrimp samples were collected. The presence of foodborne viruses were assessed by the real-time PCR. Forty-nine out of 320 (15.31%) fish and shrimp samples were positive for foodborne viruses. Distribution of hAV, NoV GI and NoV GII amongst all studied samples were 0.93%, 5.93% and 8.43%, respectively. hEV and RoV viruses were not found in studied samples. Parastromateus niger and Scomberomorus commerson fish and Penaeus monodon shrimp were the most frequently contaminated samples. Simultaneous incidence of hAV and NoV GI and hAV and NoV GII were 0.31% and 0.93%, respectively. Distribution of foodborne viruses in samples collected through spring, summer, autumn and winter seasons were 14.28%, 9.33%, 11.76% and 24.44%, respectively. Findings revealed that the incidence of foodborne viruses was significantly associated with seafood species and also season of sampling.(AU)

Vírus transmitidos por alimentos, incluindo hepatite A (HAV), norovírus (NoV), rotavírus (RoV) e hepatite E (HEV) são facilmente transmitidos através de frutos do mar contaminados. Esta pesquisa foi realizada para avaliar a incidência de RoV, NoV GI e GII, hAV e hEV em amostras de peixes e camarões capturadas no Golfo Pérsico, Irã. Foram coletadas 300 amostras de peixes e camarões. A presença de vírus transmitidos por alimentos foi avaliada por PCR em tempo real. Quarenta e nove das 320 amostras de peixes e camarões (15,31%) foram positivas para vírus transmitidos por alimentos. A distribuição de hAV, NoV GI e NoV GII entre as amostras estudadas foi 0,93%, 5,93% e 8,43%, respectivamente. Os vírus hEV e RoV não foram encontrados nas amostras estudadas. Os peixes Parastromateus niger e Scomberomorus commerson e o camarão Penaeus monodon foram as amostras mais frequentemente contaminadas. A incidência simultânea de hAV e NoV GI, e hAV e NoV GII foi de 0,31% e 0,93%, respectivamente. A distribuição dos vírus transmitidos por alimentos nas amostras coletadas na primavera, verão, outono e inverno foi de 14,28%, 9,33%, 11,76% e 24,44%, respectivamente. Os resultados demonstram que a incidência de vírus transmitidos por alimentos foi significativamente associada às espécies de frutos do mar e também à época da amostragem.(AU)

Hepatitis A / Hepatitis A

Resumen El virus de la hepatitis A ha estado clásicamente relacionado con el mecanismo de transmisión fecal-oral, característica de países endémicos. El aumento de las condiciones higiénicas en nuestro entorno había supuesto una importante disminución de los casos de infección por estos patógenos. Sin embargo, en la actualidad, su epidemiología esta cambiando debido a nuevas vías de contagio en Europa. En el caso de la hepatitis A, están aumentando los casos debidos a la transmisión por vía sexual, especialmente en hombres que tienen sexo con hombres. Los cambios descritos deberían promover la implantación de nuevas estrategias de diagnóstico, manejo y prevención. La hepatitis aguda por virus de hepatitis A usualmente sigue un curso corto, benigno y autolimitado sin ocasionar una hepatitis crónica, sin embargo en algunos casos puede manifestarse mediante formas atípicas.

Abstract Hepatitis A virus has been classically linked to the fecal-oral transmission mechanism, characteristic of endemic countries. The increase in hygiene conditions in our environment had led to a significant decrease in cases of infection by these pathogens. However, the epidemiology of these infections is currently changing due to new routes of transmission in Europe. In the case of hepatitis A, cases due to sexual transmission are increasing, especially among men who have sex with men. The changes described should promote the implementation of new strategies for the diagnosis, management and prevention of these diseases. Acute hepatitis due to the hepatitis A virus usually has a short, benign and self-limited course, without causing chronic hepatitis. However, some cases have an atypical presentation.

Trombocitopenia asociada al virus de la Hepatitis A: Reporte de 3 casos / Thrombocytopenia associated to the Hepatitis A virus: report of 3 cases

La trombocitopenia asociada al virus de la hepatitis A es un cuadro clínico poco frecuente. Esta asociación se caracteriza por tener dos formas de presentación: aislada o acompañada de síntomas sistémicos, siendo un signo en común la presencia de hepatitis. La alteración del sistema inmunológico, demostrado por la presencia de anticuerpos, sería la principal etiología. Se presentan tres casos, dos de ellos con síntomas sistémicos y uno con clínica aislada. (AU)

The thrombocytopenia associated to the Hepatitis A virus is a rare clinical case. According to published cases, this association is characterized by two forms of presentation: isolated or accompanied by systemic symptoms, a common sign being the presence of hepatitis. The alteration of the immune system, demonstrated by the presence of antibodies, would be the main etiology of this pathology. Three cases are presented, two of them with systemic symptoms and one with isolated clinical symptoms. (AU)

Solubility as a limiting factor for expression of hepatitis A virus proteins in insect cell-baculovirus system

The use of recombinant proteins may represent an alternative model to inactivated vaccines against hepatitis A virus (HAV). The present study aimed to express the VP1 protein of HAV in baculovirus expression vector system (BEVS). The VP1 was expressed intracellularly with molecular mass of 35 kDa. The VP1 was detected both in the soluble fraction and in the insoluble fraction of the lysate. The extracellular expression of VP1 was also attempted, but the protein remained inside the cell. To verify if hydrophobic characteristics would also be present in the HAV structural polyprotein, the expression of P1-2A protein was evaluated. The P1-2A polyprotein remained insoluble in the cellular extract, even in the early infection stages. These results suggest that HAV structural proteins are prone to form insoluble aggregates. The low solubility represents a drawback for production of large amounts of HAV proteins in BEVS.

Cynomolgus monkeys (Macaca fascicularis) experimentally infected with B19V and hepatitis A virus: no evidence of the co-infection as a cause of acute liver failure

This study was conducted to analyse the course and the outcome of the liver disease in the co-infected animals in order to evaluate a possible synergic effect of human parvovirus B19 (B19V) and hepatitis A virus (HAV) co-infection. Nine adult cynomolgus monkeys were inoculated with serum obtained from a fatal case of B19V infection and/or a faecal suspension of acute HAV. The presence of specific antibodies to HAV and B19V, liver enzyme levels, viraemia, haematological changes, and necroinflammatory liver lesions were used for monitoring the infections. Seroconversion was confirmed in all infected groups. A similar pattern of B19V infection to human disease was observed, which was characterised by high and persistent viraemia in association with reticulocytopenia and mild to moderate anaemia during the period of investigation (59 days). Additionally, the intranuclear inclusion bodies were observed in pro-erythroblast cell from an infected cynomolgus and B19V Ag in hepatocytes. The erythroid hypoplasia and decrease in lymphocyte counts were more evident in the co-infected group. The present results demonstrated, for the first time, the susceptibility of cynomolgus to B19V infection, but it did not show a worsening of liver histopathology in the co-infected group.

SEROLOGICAL DETECTION OF HEPATITIS A VIRUS IN FREE-RANGING NEOTROPICAL PRIMATES (Sapajus spp., Alouatta caraya) FROM THE PARANÁ RIVER BASIN, BRAZIL

Nonhuman primates are considered as the natural hosts of Hepatitis A virus (HAV), as well as other pathogens, and can serve as natural sentinels to investigate epizootics and endemic diseases that are of public health importance. During this study, blood samples were collected from 112 Neotropical primates (NTPs) (Sapajus nigritus and S. cay, n = 75; Alouatta caraya, n = 37) trap-captured at the Paraná River basin, Brazil, located between the States of Paraná and Mato Grosso do Sul. Anti-HAV IgG antibodies were detected in 4.5% (5/112) of NTPs, specifically in 6.7% (5/75) of Sapajus spp. and 0% (0/37) of A. caraya. In addition, all samples were negative for the presence of IgM anti-HAV antibodies. These results suggest that free-ranging NTPs were exposed to HAV within the geographical regions evaluated.

Expressão heteróloga de proteínas do vírus da Hepatite A e avaliação da imunogenicidade / Heterologous expression of hepatitis a virus proteins and immunogenicity evaluation

O vírus da hepatite A (HAV) é o principal agente etiológico das hepatites virais agudas e estima-se que ocasione 1,5 milhão de novas infecções no mundo anualmente. Apesar da eficácia apresentada pelas vacinas comerciais, a replicação do HAV em cultura de células é lenta e apresenta baixo rendimento, o que torna a sua produção difícil e dispendiosa. Nesse contexto, o uso de proteínas recombinantes do HAV pode representar uma alternativa ao modelo de vacina existente. O presente trabalho teve como objetivo expressar e avaliar a imunogenicidade das partículas virais destituídas de ácido nucleico (VLPs) e da proteína VP1 do HAV. As VLPs foram geradas a partir do sistema baculovírus/células de inseto através da infecção de células de inseto com baculovírus recombinantes contendo as regiões P1-2A e P3 do genoma do HAV. A poliproteína P1-2A foi expressa, clivada e se organizou em estruturas que continham epitopos conformacionais de neutralização. Partículas com características similares ao HAV foram identificadas por microscopia eletrônica, sugerindo que as proteínas expressas se montaram em VLPs. Em paralelo, a VP1 foi expressa nos sistemas baculovírus/células de inseto e Escherichia coli. Níveis mais elevados de expressão foram obtidos em E. coli, o que consequentemente aumentou a taxa de recuperação da proteína purificada. A VP1 derivada de E. coli foi utilizada nos ensaios de antigenicidade e mostrou reatividade frente aos soros de pacientes infectados pelo HAV, o que demonstra seu potencial como um marcador para diagnóstico. Para os estudos de imunogenicidade, a VP1 derivada de E. coli foi combinada a dois adjuvantes, o hidróxido de alumínio (Al(OH)3) e o adjuvante a base de saponina...

The hepatitis A virus (HAV) is the primary etiological agent of acute viral hepatitis and it is estimated to cause 1.5 million of new infections each year worldwide. Despite the effectiveness of commercial vaccines, the replication of HAV in cell culture is slow and haslow yield, which makes it difficult and expensive to manufacture. In this context, the use of recombinant HAV proteins could represent an alternative model to the existing vaccines. This study aimed to express and evaluate the immunogenicity of virus-like-particles (VLPs) and VP1 protein of HAV. The VLPs were generated using the baculovirus/insect cell expression system by the infection of insect cells with recombinant baculovirus containing HAV P1-2A and P3 regions. The P1-2A polyprotein was successfully expressed, cleaved and organized into structures that contained neutralizing conformational epitopes. HAV-like particles were identified by electron microscopy, suggesting that the expressed proteins were assembled into VLPs. In parallel, VP1 was expressed in both baculovirus/insect cell and Escherichia coliexpression systems. Higher protein levels were obtained in E. coli, which consequently increased the recovery rate after protein purification. The E. coli-derived VP1 was then used in antigenicity assays and showed reactivity against sera from patients infected with HAV, demonstrating its potential as a diagnostic marker. For immunogenicity studies, the E. coli-derived VP1 was combined with two adjuvants, aluminum hydroxide (Al(OH)3) and the saponin-based adjuvant...

Using immunoglobulin Y as an alternative antibody for the detection of hepatitis A virus in frozen liver sections

An increasing amount of research has been conducted on immunoglobulin Y (IgY) because the use of IgY offers several advantages with respect to diagnostic testing, including its easy accessibility, low cost and translatability to large-scale production, in addition to the fact that it can be ethically produced. In a previous work, immunoglobulin was produced and purified from egg yolks (IgY) reactive to hepatitis A virus (HAV) antigens. In the present work, this anti-HAV-specific IgY was used in an indirect immunofluorescence assay to detect viral antigens in liver biopsies that were obtained from experimentally infected cynomolgus monkeys. Fields that were positive for HAV antigen were detected in liver sections using confocal microscopy. In conclusion, egg yolks from immunised hens may be a reliable source for antibody production, which can be employed for immunological studies.

Infección por el virus de la hepatitis A: epidemiología y diversidad genética / Hepatitis A virus infection: Epidemiology and genetic diversity / Infecção pelo vírus da hepatite A: epidemiologia e diversidade genética

La infección por el virus de la hepatitis A es un problema global de salud pública. El virus está ampliamente distribuido y es la principal causa de hepatitis aguda de transmisión entérica en Latinoamérica. La partícula viral es estable en el medio ambiente y conserva su infectividad por varias semanas, lo que facilita su transmisión por agua y alimentos contaminados. Mundialmente se han descrito distintos patrones epidemiológicos, que pueden cambiar en el tiempo al modificarse variables socioeconómicas en la población como las condiciones sanitarias básicas y la vacunación. Esto deja al descubierto nuevas poblaciones susceptibles a la infección. En Latinoamérica se ha descrito la circulación del genotipo I y los subgenotipos A y B, pero se requieren más investigaciones que aporten el conocimiento necesario para gestionar planes de prevención y control para la disminución mundial de la prevalencia de la infección. Para este artículo se hizo una revisión de la literatura en las bases de datos SciELO, PubMed y ScienceDirect bajo los términos de búsqueda ''Virus de la hepatitis A'', ''Epidemiología'', ''Seroprevalencia'' e ''Infección''. De los resultados obtenidos se incluyeron únicamente las publicaciones en inglés y español que describieran estudios epidemiológicos y moleculares de interés en Latinoamérica.

Hepatitis A virus infection is a global public health problem. The virus has a wide range of distribution and it is the main cause of acute hepatitis transmitted by the enteric route in Latin America. The viral particle is stable under environmental conditions and conserves its infectivity for several weeks, enabling its transmission by contaminated water and food. Worldwide, different epidemiological patterns have been identified, which may change over time by modification of social and economic variables in the population such as vaccination and the improvement of hygiene and primary health conditions. This leaves new populations susceptible to infection. In Latin America the circulation of genotype I and subgenotypes A and B has been described, but more research is needed to provide the knowledge needed to manage the prevention and control plans for the worldwide reduction of the prevalence of infection. For this paper, a literature review was performed on the SciELO, PubMed and ScienceDirect databases under the search terms "Hepatitis A", "Epidemiology," "Seroprevalence" and "Infection." From the results obtained, only papers published in English and Spanish to describe epidemiological and molecular studies of interest in Latin America were included.

A infecção pelo vírus da hepatite A é um problema global de saúde pública. O vírus está amplamente distribuído e é a principal causa de hepatite aguda de transmissão entérica na América Latina. A partícula viral é estável no médio ambiente e conserva sua infecciosidade por várias semanas, o que facilita sua transmissão por água e alimentos contaminados. Mundialmente se descreveram diferentes padrões epidemiológicos, que podem mudar no tempo ao modificar- se variáveis socioeconômicas na população como as condições sanitárias básicas e a vacinação. Isto deixa ao descoberto novas populações susceptíveis à infecção. Na América Latina se descreveu a circulação do genótipo I e os sub-genótipos A e B, mas são necessárias mais investigações que contribuam o conhecimento necessário para gerir planos de prevenção e controle para a diminuição mundial da prevalência da infecção. Para este artigo se fez uma revisão da literatura nas bases de dados SciELO, Pub- Med e ScienceDirect sob os termos de busca ''Vírus da hepatite A'', ''Epidemiologia'', ''Seroprevalência'' e ''Infecção''. Dos resultados obtidos se incluíram unicamente os estudos publicados em inglês e espanhol que descrevessem estudos epidemiológicos e moleculares de interesse na América Latina.

Prevalencia de anticuerpos totales contra el virus de la hepatitis A (VHA) en individuos adultos de la ciudad de Córdoba

Argentina es considerada un país de endemicidad intermedia para el virus de la hepatitis A (VHA). Debido a la introducción de la vacuna al calendario nacional (2005), es notable la reducción de notificaciones de casos clínicos por este virus. Sin embargo, en los últimos años el Ministerio de Salud de la Nación reportó un desplazamiento de la incidencia de casos, siendo los más afectados los adolescentes y adultos jóvenes. Como en Córdoba no existían datos actualizados de la prevalencia de anticuerpos en la población general adulta, el objetivo del trabajo fue proveer información actualizada sobre el estado inmunitario específico para VHA en individuos adultos de la ciudad de Córdoba después de cuatro años de la presentación oficial de la vacuna. Para ello, se realizó un estudio retrospectivo de seroprevalencia en muestras de sueros de 416 individuos adultos sanos residentes en Córdoba capital, sin antecedentes previos de vacunación y que fueron atendidos en centros de atención de salud durante septiembre de 2009 y septiembre 2010. Las muestras se clasificaron por grupos etarios y condiciones socio-económicas. La asociación de la prevalencia con la edad y la variable socioeconómica se determinó mediante modelos de regresión spline, en el marco de los modelos aditivos generalizados. La prevalencia global de anti-VHA fue del 73,5 %...

ABSTRACT: Hepatitis A virus (HAV) has shown intermediate endemicity in Argentina, but notification of clinical cases has decreased since the introduction of the vaccine in 2005. However, in recent years the Ministry of Health of Argentina reported a shift in the incidence of cases, being the most affected adolescents and young adults. In Cordoba, no data updated on the prevalence of antibodies in general adult population. So the objective was to provide information on HAV immune status of the adult population of Córdoba city after four years of the official introduction of the vaccine. The prevalence of anti-HAV was determined by EIA in 416 serum samples of people (without prior vaccination) from Córdoba city (sept2009–sept2010). Spline regression models were estimated under generalized additive models. In Córdoba, the global prevalence of anti-HAV was 73.5%...

Detección del virus de la Hepatitis A en dos muestras de agua del Río Sechura, usando transcriptasa-reversa PCR en tiempo real / Detection of Hepatitis A Virus in two water samples from Sechura river by using Real-Time Quantitative Reverse Transcription PCR

El Virus de la Hepatitis A (VHA) es un patógeno de transmisión fecal-oral, y el agua es un medio importante para su diseminación. El Río Sechura (Piura, Perú) desemboca al mar y representaría una fuente de contaminación a las playas Chulliyachi, San Pedro y San Pablo en donde se extraen moluscos bivalvos. Objetivos: Detectar VHA en muestras de agua del río Sechura mediante técnicas moleculares. Métodología: Se recogió en total 24 muestras de agua en tres puntos geográficos del río Sechura, en intervalos de cada 15 días durante 4 meses (de mayo a setiembre de 2013). Cada muestra se trasladó en botellas estériles de 1 litro. A cada botella se le realizó un proceso de concentración de virus en agua, luego extracción de ARN, y RT-PCR en tiempo real. Resultados y Conclusiones: Dos muestras (2/24, 8.3%) resultaron positivas a VHA. Este es el primer reporte de presencia de VHA en agua de río en el Perú.

Hepatitis A virus (HAV) is a fecal-oral transmitted pathogen, and water is an important transmission way. This study considered a possible role in the HAV contamination of aquaculture areas by the Sechura River (Piura, Peru). In addition, this river gets into the sea and represents a source of contamination to Chulliyachi, San Pedro and San Pablo beaches where bivalve mollusks are collected. Objective: To detect HAV in waters of Sechura River by using molecular techniques. Methodology: Twenty four samples were collected from three different spots of the river. The samples were taken every two weeks during four months (from May to September 2013), these were transferred in 1 L sterile bottles to the Laboratory, then they were analyzed by a process of concentration of virus in water, thereafter RNA extraction and real time RT-PCR. Results and Conclusion: Two samples (2/24, 8.3%) were positive to HAV. This is the first report of presence of HAV in river waters in Perú.

Detection of replication-defective hepatitis A virus based on the correlation between real-time polymerase chain reaction and ELISA in situ results

ELISA in situ can be used to titrate hepatitis A virus (HAV) particles and real-time polymerase chain reaction (RT-PCR) has been shown to be a fast method to quantify the HAV genome. Precise quantification of viral concentration is necessary to distinguish between infectious and non-infectious particles. The purpose of this study was to compare cell culture and RT-PCR quantification results and determine whether HAV genome quantification can be correlated with infectivity. For this purpose, three stocks of undiluted, five-fold diluted and 10-fold diluted HAV were prepared to inoculate cells in a 96-well plate. Monolayers were then incubated for seven, 10 and 14 days and the correlation between the ELISA in situ and RT-PCR results was evaluated. At 10 days post-incubation, the highest viral load was observed in all stocks of HAV via RT-PCR (10(5) copies/mL) (p = 0.0002), while ELISA revealed the highest quantity of particles after 14 days (optical density = 0.24, p < 0.001). At seven days post-infection, there was a significant statistical correlation between the results of the two methods, indicating equivalents titres of particles and HAV genome during this period of infection. The results reported here indicate that the duration of growth of HAV in cell culture must be taken into account to correlate genome quantification with infectivity.

The efficiency of concentration methods used to detect enteric viruses in anaerobically digested sludge

The presence of enteric viruses in biosolids can be underestimated due to the inefficient methods (mainly molecular methods) used to recover the viruses from these matrices. Therefore, the goal of this study was to evaluate the different methods used to recover adenoviruses (AdV), rotavirus species A (RVA), norovirus genogroup II (NoV GII) and the hepatitis A virus (HAV) from biosolid samples at a large urban wastewater treatment plant in Brazil after they had been treated by mesophilic anaerobic digestion. Quantitative polymerase chain reaction (PCR) was used for spiking experiments to compare the detection limits of feasible methods, such as beef extract elution and ultracentrifugation. Tests were performed to detect the inhibition levels and the bacteriophage PP7 was used as an internal control. The results showed that the inhibitors affected the efficiency of the PCR reaction and that beef extract elution is a suitable method for detecting enteric viruses, mainly AdV from biosolid samples. All of the viral groups were detected in the biosolid samples: AdV (90%), RVA, NoV GII (45%) and HAV (18%), indicating the viruses' resistance to the anaerobic treatment process. This is the first study in Brazil to detect the presence of RVA, AdV, NoV GII and HAV in anaerobically digested sludge, highlighting the importance of adequate waste management.

An immunoenzymatic assay for the diagnosis of hepatitis A utilising immunoglobulin Y

The detection of anti-hepatitis A virus (HAV) antibody levels by diagnostic kits in the convalescent period of disease generally use immunoglobulin G (IgG), which is expensive. An alternative to IgG is immunoglobulin Y (IgY), an immunoglobulin antibody encountered in birds and reptiles. The aim of this study was to develop a competitive immunoenzymatic assay to measure total anti-HAV antibody levels using anti-HAV IgY as the capture and conjugated immunoglobulins. For this purpose, anti-HAV IgY was conjugated to horseradish peroxidase (HRP) and the optimal dilution of HRP-conjugated antibodies was evaluated to establish the competitive immuneenzymatic assay. The results obtained from our "in-house" assay were plotted on a receiver operator curve, which showed a sensitivity of 95% and a specificity of 98.8%, demonstrating that a competitive anti-HAV IgY immunoenzymatic assay developed "in house" could be used as an alternative to commercial assays that utilise IgG.

The depuration dynamics of oysters (Crassostrea gigas) artificially contaminated with hepatitis A virus and human adenovirus

Within the country of Brazil, Santa Catarina is a major shellfish producer. Detection of viral contamination is an important step to ensure production quality and consumer safety during this process. In this study, we used a depuration system and ultraviolet (UV) disinfection to eliminate viral pathogens from artificially infected oysters and analysed the results. Specifically, the oysters were contaminated with hepatitis A virus (HAV) or human adenovirus type 5 (HAdV5). After viral infection, the oysters were placed into a depuration tank and harvested after 48, 72 and 96 h. After sampling, various oyster tissues were dissected and homogenised and the viruses were eluted with alkaline conditions and precipitated with polyethylene glycol. The oyster samples were evaluated by cell culture methods, as well as polymerase chain reaction (PCR) and quantitative-PCR. Moreover, at the end of the depuration period, the disinfected seawater was collected and analysed by PCR. The molecular assays showed that the HAdV5 genome was present in all of the depuration time samples, while the HAV genome was undetectable after 72 h of depuration. However, viral viability tests (integrated cell culture-PCR and immunofluorescence assay) indicated that both viruses were inactivated with 96 h of seawater recirculation. In conclusion, after 96 h of UV treatment, the depuration system studied in this work purified oysters that were artificially contaminated with HAdV5 and HAV.

Seroprevalence of hepatitis A immunity among brazilian adult patients with liver cirrhosis: is HAV vaccination necessary?

BACKGROUND: Patients with chronic liver disease have a higher risk of fulminant hepatitis when infected with hepatitis A virus, and vaccination of these patients against such infection is recommended. In Brazil, mainly in the South and Southeast regions, the epidemiology of hepatitis A (HA) has shifted from high to intermediate endemicity, which would have implication on policy of HA vaccination for these populations. OBJECTIVE: To verify the prevalence of HA immunity in adult patients with liver cirrhosis (LC), in Uberlândia MG, a city of Southeastern Brazil. METHODS: Between December 2005 and December 2006, 106 patients with LC were consecutively evaluated. In addition, 75 individuals without LC or alcoholism were evaluated (control group - CG). RESULTS: Total anti-HAV (ELISA methods) was positive in 104 (98.1 percent) patients with LC (82 men, 24 women; mean age, 53.3 ± 11.9 years) and in 74 (98.7 percent) individuals of the CG (55 men, 20 women; mean age, 47 ± 11.6 years), p > 0.05. CONCLUSIONS: For patients with chronic liver disease, in the geographic regions and age groups evaluated, routine vaccination against hepatitis A is not recommended. Moreover, the serum determination of total anti-HAV, used to assess immunity, is five times cheaper than vaccination against hepatitis A and, for this reason, should precede vaccination.

Seroprevalencia del virus de la hepatitis A en niños de 1 a 15 años en un hospital universitario / Seroprevalence of the hepatitis A virus in children from 1 to 15 years old in a university hospital

Introducción. La hepatitis A es una enfermedad infectocontagiosa causada por un virus ARN no encapsulado de la familia Picornaviridae y del género Hepatovirus, que se trasmite por vía fecal-oral, bien sea de persona a persona o en epidemias originadas por una fuente común. Objetivo. Se estimo la seroprevalencia de anticuerpos de tipo IgG contra el virus de la hepatitis A en niños de 1 a 15 años, atendidos en un hospital universitario, como parte de un estudio cooperativo nacional. Métodos. Se realizó un estudio descriptivo y prospectivo, entre junio y noviembre de 2007. Los niveles de anticuerpos se detectaron mediante un inmunoensayo enzimático de micropartículas. A cada participante del estudio se le hizo una encuesta de riesgo con las variables objeto del estudio. Resultados. Se estudiaron 422 niños. La prevalencia global de anticuerpos contra el virus de la hepatitis A fue de 29,1%: 37,1% en el grupo de 5 a 9 años, 36,1%, en el de 10 a 15 y 13,8%, en el de 1 a 4 años. La mayor proporción de prevalencia de anticuerpos se encontró en los niños de estrato socioeconómico más bajo: 44,2% para el estrato 1 y 27,9% para el estrato 2. Discusión. En este estudio se encontró una seroprevalencia de anticuerpos para hepatitis A más baja en menores de 5 años, lo que puede indicar una transición del patrón epidemiológico hacia un nivel intermedio. La prevalencia fue mayor en los niños de estratos socioeconómicos bajos, lo que puede estar en relación con el hacinamiento y las malas prácticas de higiene.

Introduction: Hepatitis A is an infectious disease caused by a non-encapsulated RNA virus of the Picornaviridae family, classified as Hepatovirus. It is transmitted by a fecal-oral route, either from person to person or in common source epidemics. Objective: The aim of this study was to estimate the seroprevalence of IgG antibodies against the hepatitis A virus in children aged 1-15 years, treated in a university hospital as part of a national collaborative study. Methods: A descriptive study was performed between June and November 2007. The antibody titers were detected by means of a Microparticle Capture Enzyme Immunoassay. A survey to identify risk factors was conducted for each participant, with additional variables under study. Results: We studied 422 children. The overall prevalence of antibodies against hepatitis A was 29.1%, with 37.1% in the group of 5 to 9 years of age, 36.1% for 10 to 15, and 13.8% for 1 to 4. The highest proportion of antibody prevalence was found in children of the lowest socioeconomic status, 44.2% for the stratum 1 and 27.9% for the stratum 2. Conclusion: The seroprevalence to hepatitis A virus was lower in children with less than five years of age, which is an indication of a transition of the epidemiological profile to an intermediate one. The prevalence was higher in children of low socioeconomic levels, which may be related to overcrowding and poor hygiene practices.

Hepatitis A / Hepatitis A

la hepatitis causada por el virus de la hepatitis A es una enfermedad aguda, frecuente a nivel mundial. Aunque permaneceendémica en países en desarrollo, las tasas de seroprevalencia en los países desarrollados continúan disminuyendo. En los niñosla infección aguda usualmente es asintomática; sin embargo, enlos adultos se pueden presentar una variedad de manifestacionesclínicas que van desde leves hasta una falla hepática fulminante,la cual afortunadamente, es muy poco frecuente. La transmisiónde virus es generalmente por la ingestión de agua y alimentos contaminados con materia fecal que está infectada con el virus. Eldiagnóstico de la hepatitis A se basa en las pruebas de laboratorio, apoyadas en la búsqueda de anticuerpos tipo IgM, específicos parael virus de la hepatitis A. La inmunoprofilaxis con gamma globulinaanti-VHA puede prevenir y atenuar la enfermedad en persona sexpuestas al virus. La vacuna por su parte, induce inmunidad a largoplazo y abre la posibilidad a la erradicación de esta enfermedad enel mundo.

Hepatitis caused by the hepatitis A virus is an acute disease, prevalent worldwide. Although endemic in developing countries, seroprevalence rates in developed countries continue to decline. In children, acute infection is usually asymptomatic; However, in adults, a variety of clinical manifestations ranging from mild to fulminant hepatic failure, which fortunately, is very rare. The virus transmission is usually by ingestion of water and food contaminated with fecal matter that is infected with the virus. Eldiagnosis of hepatitis A is based on laboratory tests, based on the search for IgM antibodies specific for the hepatitis A virus. Immunoprophylaxis with gamma globulin-VHA can prevent and attenuate the disease in people exposed to the virus. The vaccine, on the other hand, induces long-term immunity and opens the possibility for the eradication of this disease in the world.