Genómica de rotavirus. Impacto en salud pública / Rotavirus genomics. Public health impact

Resumen: Con la introducción de las vacunas de rotavirus Rotarix (RV1) o RotaTeq (RV5) en programas nacionales de vacunación de diversos países, surgió la preocupación de que la presión inmune generada condujera al aumento en la prevalencia de genotipos virales no incluidos en las vacunas, o bien del surgimiento de nuevas cepas que pudieran escapar a la respuesta inmune protectora inducida por la vacunación. La variación natural de los rotavirus ha hecho que sea muy difícil distinguir si el cambio en las cepas circulantes se debe a la presión selectiva impuesta por las vacunas o bien a la fluctuación natural de las cepas. Si acaso ha habido una presión selectiva, ésta ha sido hasta ahora baja. Sin embargo, es importante mantener la vigilancia epidemiólogica y poner atención al surgimiento de cepas resistentes a la inmunidad, en particular en países en desarrollo en los que se ha descrito una mayor diversidad viral.

Abstract: With the introduction of rotavirus vaccines Rotarix (RV1) or RotaTeq (RV5) in the immunization programs of an increasing number of countries, there is concern that the immune selection pressure induced will cause an increase in the prevalence of virus genotypes not included in the vaccine formulation, or to the appearance of novel rotavirus strains that could evade the protective immune response. The natural fluctuation of rotaviruses makes it difficult to distinguish if the change in the circulating strains is due to the vaccine selective pressure or to the natural diversity fluctuation of viruses. If there has been a selective pressure, it has been low so far. However, it is important to keep an epidemiological surveillance and pay attention to the emergence of strains that are resistant to the vaccine, in particular in those countries where the viral diversity has been shown to be higher.

Knowledge about bacterial and viral pathogens present in wild mammals in Chile: a systematic review

This study organizes all available information about viral and bacterial pathogens of wild mammals in Chile. This was done in order to identify pathogens that have been well-documented and recognize those that have not been properly studied, determine the number of articles that have been published annually about this topic and identify regions in Chile that concentrate the highest and lowest number of studies concerning viral and bacterial pathogens. A total of 67 scientific articles published in peer-reviewed journals from 1951 to 2018 were selected for revision. Results indicate that the number of publications has increased per decade but there are years in which no articles were published. Most studies addressed Leptospira, rabies, hantavirus, Mycobacterium avium paratuberculosis (MAP) and distemper. Rodentia, Carnivora, Chiroptera and Cetartiodactyla were the most studied mammal orders. Information about presence/absence of pathogens was found for 44 wild mammal species. Research was mainly carried out in central and southern Chile and the most commonly employed methods for pathogen diagnosis were serology and molecular techniques. Overall, research in wild mammals has been directed towards the evaluation of zoonotic diseases, while vector-borne and non-zoonotic diseases have been mostly neglected by the scientific community over the years.

Conocimiento acerca de los patógenos virales y bacterianos presentes en mamíferos silvestres en Chile: una revisión sistemática / Knowledge about viral and bacterial pathogens present in wild mammals in Chile: a systematic review

Resumen Este estudio organiza toda la información disponible acerca de los patógenos virales y bacterianos de mamíferos silvestres en Chile. Esto fue realizado con el objetivo de identificar patógenos que han sido bien documentados y reconocer aquellos que no han sido apropiadamente estudiados, determinar el número de artículos que han sido publicados anualmente acerca de este tópico e identificar las regiones en Chile que han concentrado el mayor y menor número de estudios relacionados con patógenos virales y bacterianos. Para lograr esto, se seleccionó para revisión un total de 67 artículos científicos publicados en revistas evaluadas por pares desde 1951 al 2018. Los resultados indican que el número de publicaciones ha incrementado por década y hay años en los cuales no se publicaron artículos. La mayoría de los estudios se relacionan con Leptospira, rabia, hantavirus, Mycobacterium avium paratuberculosis (MAP) y distémper. Rodentia, Carnivora, Chiroptera y Cetartiodactyla fueron los órdenes de mamíferos más estudiados. Información acerca de la presencia/ausencia de patógenos fue encontrada en 44 especies de mamíferos silvestres. La mayor parte de las investigaciones buscaron patógenos en Chile sur y central y los métodos de diagnóstico más empleados para el diagnóstico de patógenos fueron serología y técnicas moleculares. En general, la investigación en mamíferos silvestres ha sido dirigida a la evaluación de enfermedades zoonóticas, mientras que aquellas enfermedades transmitidas por vectores y enfermedades no zoonóticas han sido mayormente ignoradas por la comunidad científica.

This study organizes all available information about viral and bacterial pathogens of wild mammals in Chile. This was done in order to identify pathogens that have been well-documented and recognize those that have not been properly studied, determine the number of articles that have been published annually about this topic and identify regions in Chile that concentrate the highest and lowest number of studies concerning viral and bacterial pathogens. A total of 67 scientific articles published in peer-reviewed journals from 1951 to 2018 were selected for revision. Results indicate that the number of publications has increased per decade but there are years in which no articles were published. Most studies addressed Leptospira, rabies, hantavirus, Mycobacterium avium paratuberculosis (MAP) and distemper. Rodentia, Carnivora, Chiroptera and Cetartiodactyla were the most studied mammal orders. Information about presence/absence of pathogens was found for 44 wild mammal species. Research was mainly carried out in central and southern Chile and the most commonly employed methods for pathogen diagnosis were serology and molecular techniques. Overall, research in Chilean wild mammals has been directed towards the evaluation of zoonotic diseases, while vector-borne and non-zoonotic diseases have been mostly neglected by the scientific community.

Evolutionary study of potentially zoonotic hepatitis E virus genotype 3 from swine in Northeast Brazil

Hepatitis E virus (HEV), an emerging virus associated with acute hepatic disease, leads to thousands of deaths worldwide. HEV has already been reported in Brazil; however, there is a lack of epidemiological and molecular information on the genetic variability, taxonomy, and evolution of HEV. It is thus unclear whether hepatitis E is a neglected disease in Brazil or it has low relevance for public health in this country. Here, for the first time, we report the presence of HEV in Northeast Brazil. A total of 119 swine faecal samples were screened for the presence of HEV RNA using real-time polymerase chain reaction (RT-PCR) and further confirmed by conventional RT-PCR; among these, two samples were identified as positive. Molecular evolution analyses based on capsid sequences revealed that the samples had close proximities to HEV sequences belonging to genotype 3 and were genetically related to subtype 3f isolated in humans. Parsimony ancestral states analysis indicated gene flow events from HEV cross-species infection, suggesting an important role of pig hosts in viral spillover. HEV's ability for zoonotic transmission by inter-species host switching as well as its possible adaptation to new animal species remain important issues for human health.

Group A rotavirus gastroenteritis: post-vaccine era, genotypes and zoonotic transmission / Gastroenterite por rotavírus do grupo A: era pós-vacinal, genótipos e transmissão zoonótica

ABSTRACT This article provides a review of immunity, diagnosis, and clinical aspects of rotavirus disease. It also informs about the changes in epidemiology of diarrheal disease and genetic diversity of circulating group A rotavirus strains following the introduction of vaccines. Group A rotavirus is the major pathogen causing gastroenteritis in animals. Its segmented RNA genome can lead to the emergence of new or unusual strains in human populations via interspecies transmission and/or reassortment events.

RESUMO Este artigo fornece uma revisão sobre imunidade, diagnóstico e aspectos clínicos da doença causada por rotavírus. Também aponta as principais mudanças no perfil epidemiológico da doença diarreica e na diversidade genética das cepas circulantes de rotavírus do grupo A, após a introdução vacinal. O rotavírus do grupo A é o principal patógeno associado à gastroenterite em animais. Seu genoma RNA segmentado pode levar ao surgimento de cepas novas ou incomuns na população humana, por meio de transmissão entre espécies e eventos de rearranjo.

Avian Influenza A [H5N1] in Egypt

Between February and March 2016, the Ministry of Health and Populations of Egypt reported 4 new human cases of avian influenza A [H5N1] infection to WHO. These are the new human cases reported in 2016 after the surge of human cases observed in 2015 in the country. With this, a total of 350 human cases of avian influenza A [H5N1] including 117 deaths [CFR: 33.4%] were reported in Egypt since 2006

Molecular detection of hepatitis E virus in feces and slurry from swine farms, Rio Grande do Sul, Southern Brazil / Detecção molecular do vírus da hepatite E em fezes e chorume de propriedades suinícolas, Rio Grande do Sul, Sul do Brasil

Hepatitis E virus (HEV) is highly disseminated among swine herds worldwide. HEV is also a threat to public health, since particularly genotypes 3 and 4 may cause acute hepatitis in human beings. No previous studies were done on the occurrence of HEV in environmental samples in Rio Grande do Sul, Brazil. In the present study, reverse transcriptase-polymerase chain reaction (RT-PCR) was employed to detect the presence of HEV in swine feces and in effluents from slurry lagoons in farms located in the municipality of Teutônia, inside the area of swine husbandry in the state. Pooled fecal samples from the floor of pig barns from 9 wean-to-finish farms and liquid manure samples were collected from the slurry lagoons from 8 of these farms. From the pooled fecal samples, 8/9 were positive for the HEV ORF1 gene by RT-PCR; all the slurry lagoon samples were positive for HEV RNA (100%). The identity of the HEV ORF1 amplicons was confirmed by sequencing belonging to HEV genotype 3, which was previously shown to be circulating in South America.

O vírus da hepatite E (HEV) é altamente disseminado entre rebanhos suínos no mundo todo. O HEV é também uma ameaça à saúde pública, já que os genótipos 3 e 4 podem causar hepatite aguda em seres humanos. Não há estudos anteriores sobre a ocorrência de HEV em amostras ambientais no Rio Grande do Sul. No presente estudo, empregou-se transcrição reversa e reação em cadeia da polimerase (RT-PCR) para detectar a presença de HEV em fezes de suínos e efluentes de lagoas de chorume em fazendas localizadas no município de Teutônia, representativo da região de maior produção de suínos no estado. Pools de amostras fecais foram coletadas a partir do chão de galpões de suínos provenientes de 9 propriedades de terminação; outra amostra de esterco líquido foi coletada das lagoas de chorume de 8 dessas fazendas. A partir das amostras fecais reunidas, 8/9 foram positivas para o gene ORF1 de HEV por PCR convencional; todas as amostras de lagoas de chorume foram positivas para RNA de HEV (100%). A identificação dos produtos de amplificação de HEV ORF1 foi confirmada por sequenciamento pertencente ao HEV genótipo 3, o qual foi previamente detectado na América do Sul.

Influenza aviar / Avian influenza

Se hace referencia a las características virológicas de la influenza aviar, expansión geográfica y migración de las aves en los Continentes, probabilidad de riesgo de pandemia en un futuro cercano, descripción clínica de la patología y terapéutica disponible, así como también a los avances preventivos y recomendaciones.

Anti-human influenza protector antibody detected in horses as a zoonotic viruses

O objetivo deste estudo foi investigar em cavalos, a incidência do vírus influenza e seu ciclo de transmissão interespécies. Portanto, levantamento sorológico foi realizado em soro de cavalos, confrontados com ambas cepas, as específicas (eqüino) e não específicas (humana) deste vírus. Sangrias de cavalos realizadas nos anos de 1999 e de 2000, forneceram soros que, após tratamento com Caolim (20%) e hemácias de galo(50%) para remoção dos anticorpos inespecíficos, foram titulados contra ambas referidas cepas, através do teste de Inibição da Hemaglutinação (recomendado pela OMS). Os resultados, demonstraram que as respostas sorológicas dos cavalos apresentaram reação cruzada entre as cepas específicas e as não específicas. As porcentagens de títulos IH obtidos foram de 62,75% e de 60,65% para as cepas específicas A/Eq1 (H7N7) e A/Eq2 (H3N8), respectivamente. E às cepas não específicas essas porcentagens foram de: 79,05% para A (H1N1), de 94,45% para A (H3N2) e de 77,75% ao tipo B. O mais relevante nestes dados comparativos com vírus influenza, foi a alta porcentagem de resposta protetora à cepa não específica comparada àquela específica, detectada nos soros eqüinos. Considerando o fato de que o tipo B, deste vírus, ser restrito à espécie humana, portanto a resposta de proteção nos cavalos sugere uma direta transmissão interspécies, como em viroses zoonóticas. Os autores relatam pela primeira vez este tipo de evento no Brasil.

Contaminación de los alimentos por virus: un problema de salud pública poco comprendido / Viral contamination of food products: a poorly understood public health problem

En todas partes del mundo han surgido epidemias de enfermedades transmitidas por los alimentos (ETA) sobre las que no existe suficiente información para guiar las acciones de las instituciones de salud pública. El presente estudio se hizo con objeto de contribuir a la diseminación de información sobre esas enfermedades, sus agentes etiológicos y su epidemiología y control. Se utilizaron datos de 61 estudios, entre ellos revisiones, descripciones de brotes y sistematización de datos. De los resultados obtenidos se pudo concluir que hay un gran problema de subregistro y falta de datos sobre estas enfermedades en los diversos países, pero los virus constituyen la segunda causa más importante de ETA en los Estados Unidos de América. Dos agentes, el virus Norwalk y el de la hepatitis A, ocuparon el quinto y sexto lugares, respectivamente, entre las causas principales de ETA, aunque el primero ocupó el primer puesto en 1982 y el segundo lugar como causa principal de enfermedades de transmisión hídrica durante el período de 1986 a 1988. A pesar de la escasez de datos al respecto, los rotavirus, poliovirus, virus de la hepatitis E, astrovirus y pequeños virus gastroentéricos también tienen importancia como agentes de ETA. En el artículo se discute también la importancia de las zoonosis víricas, especialmente de las fiebres hemorrágicas transmitidas por excretas de roedores y las encefalitis víricas transmitidas por garrapatas (fiebre difásica de la leche). Asimismo se presenta la polémica sobre la enfermedad de las vacas locas y su posible transmisión por los alimentos, además de los cuidados alimentarios relacionados con el sida y otras infecciones víricas. Por último, se describen los procedimientos de prevención y control de las ETA víricas