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.

Evidence of bovine viral diarrhea virus transmission by back pond water in experimentally infected piglets / Evidência da transmissão do vírus da diarreia viral bovina através da lâmina d'água em leitões experimentalmente infectados

Swine can be infected by bovine viral diarrhea virus (BVDV). However, transmission routes among pigs are still unknown. The objective of the present study was to induce experimental infection of BVDV-1 in weaned piglets and to assess the potential transmission through pen back pond water, used to facilitate heat exchange of the pigs housed in barns. Two repetitions (BP1 and BP 2) were performed using 12 piglets proven to be free BVDV (n=6 per repetition) allocated into three groups: control, sentinels and infected with two piglets each. The piglets were placed in stainless steel isolators. The infected group received an inoculum containing BVDV-1, Singer strain. The piglets remained in the cabinets for 25 days, during which samples of nasal swab were collected daily and blood sampled weekly. At the end, the piglets were euthanized, necropsied and organ fragments were collected for histopathology, immunohistochemistry and RT-PCR. In the first experiment (BP1) the infected animals shed the virus between days 6 and 21 post-infection. Regarding the sentinel group, shedding occurred in only one piglet, on the 20th day after infection, and seroconversion was observed on the 25th day post-infection. In BP2, infected piglets I3 and I4 shed the virus on days 4 and 21 post-infection, respectively. Only one sentinel piglet (S3) she the virus on day 13 post-infection. Therefore, it was concluded that pigs can become infected with BVDV-1 and shed potentially infectious viral particles consequently, being able to transmit the virus to other pigs through back pond water.(AU)

Os suínos podem ser infectados pelo vírus da diarreia viral bovina (BVDV). No entanto, as vias de transmissão entre os suínos são ainda desconhecidas. O objetivo do presente estudo foi induzir a infecção experimental de BVDV-1 em leitões desmamados e avaliar a potencial transmissão pela lâmina d'água, que ajuda na troca de calor dos suínos alojados em baias. Duas repetições do experimento (BP1 e BP2) foram realizadas com 12 animais comprovadamente livres de BVDV (n=6 por repetição) alocados em três grupos: controle, sentinelas e infectados, com dois animais cada. Os animais foram mantidos em isoladores de aço inoxidável. O grupo infectado recebeu um inóculo contendo BVDV-1, estirpe Singer. Os animais permaneceram nos isoladores durante 25 dias e, durante esse período, amostras de suabe nasal foram coletadas diariamente e sangue coletado semanalmente. No final, os animais foram eutanasiados, necropsiados e fragmentos de órgãos foram coletados para histopatologia, imuno-histoquímica e RT-PCR. No primeiro experimento (BP1), os animais infectados excretaram partículas virais entre os dias 6 e 21 pós-infecção. Quanto ao grupo sentinela, a excreção ocorreu apenas em um animal, no 20º dia pós-infecção, e a soroconversão foi observada no 25º dia pós-infecção. Na BP2, os animais infectados I3 e I4 excretaram partículas virais nos dias 4 e 21 pós-infecção, respectivamente. Apenas um animal sentinela (S3) apresentou excreção no dia 13 pós-infecção. Concluiu-se que os suínos podem se infectar com BVDV-1 e excretar partículas virais potencialmente infecciosas, sendo capazes de transmitir o vírus a outros suínos através da lâmina d'água.(AU)

Detección serológica de Brucella suis, virus de influenza y virus de la enfermedad de Aujeszky en criaderos porcinos familiares de menos de 100 madres en Argentina / Serological detection of Brucella suis, influenza virus and Aujeszky's disease virus in backyard and small swine holders in Argentina

Los criaderos porcinos de menos de 100 madres representan más del 99% de los de todo el país; sin embargo, existen escasos reportes sobre su situación sanitaria y productiva. Se recabó información productiva y se tomaron muestras para detectar anticuerpos contra Brucella suis (Bs), virus de la enfermedad de Aujeszky (VA) y virus de influenza (VI) en 68 establecimientos de menos de 100 madres ubicados en la región norte, centro y sur del país. El 80% de los establecimientos fueron positivos al VI H1 pandémico 2009, el 11% al H3 clúster 2, mientras que el 11,7% presentó anticuerpos contra el VA y el 6% contra Bs. Ninguno de los productores conocía los factores de riesgo para la transmisión de enfermedades del cerdo al humano. El 47% compra sus reproductores a pares o en ferias. En lo que respecta a normas de bioseguridad, solo el 16% de los establecimientos tenía cerco perimetral y el 37% de las granjas contaba con asesoramiento veterinario. Los resultados de este estudio demuestran que la caracterización productiva y el relevamiento sanitario son de suma importancia para mejorar la productividad y reducir el riesgo de transmisión de enfermedades. El conocimiento de la situación sanitaria y de los factores de riesgo es necesario para conseguir un mejor control y la erradicación de enfermedades en sistemas de baja tecnificación. Se deberían llevar a cabo estudios más representativos a nivel país para detectar los agentes circulantes y, sobre la base de esta información, implementar medidas de prevención y control.

Farmers raising less than 100 sows represent more than 99% of swine producers in Argentina, although little is known about their sanitary status and productive characteristics in the country. Sanitary and productive information was obtained. Furthermore, samples for serological studies were taken to detect antibodies against Brucella suis (Bs), Aujeszky's disease virus (AV) and influenza virus (IV) in 68 backyard and small producers with less than 100 sows located in the north, central and south regions of Argentina. Antibodies against H1 pandemic were detected in 80% of the farms while 11%, 11.7% and 6.0% of the producers were positive to influenza H3 cluster 2, AV and Bs, respectively. None of the producers was aware of the risk factors concerning the transmission of diseases from pigs to humans. A percentage of 47% of them buy pigs for breeding from other farmers and markets. With regard to biosecurity measures, only 16% of the farms had perimeter fences. The results of this study demonstrate that productive characterization and disease surveys are important to improve productivity and to reduce the risk of disease transmission among animals and humans. The study of sanitary status and risk factors is necessary for better control and eradication of diseases in backyard or small producers. More representative studies at country level should be carried out to detect the pathogensthat circulate and, with this knowledge, to implement prevention and control measures.

Testing pigs of non-technified rearing farms for serum antibodies against Taenia solium in a region of the state of São Paulo, Brazil / Anticorpos séricos contra Taenia solium em suínos de criações não tecnificadas em uma região do Estado de São Paulo, Brasil

Taenia solium is a zoonotic tapeworm of great importance in developing countries, due to the occurrence of human taeniasis and cysticercosis. Pigs have an important role in the biological cycle of the parasite as intermediate hosts. The scientific literature has been describing risk factors associated with the occurrence of this disease that must be avoided in countries with poor sanitation, in order to reduce the exposure of swine to the parasite eggs. This research focused on testing pigs of non-technified rearing farms for serum antibodies against Taenia solium in the region of Jaboticabal municipality, in the state of São Paulo, Brazil. The found prevalence was 6.82% (CI 95% 4.18 - 9.45) at animal level and 28.87% (CI 95% 16.74 - 40.40) at herd level. These figures are probably associated with low technification adoption during animal rearing in the studied area, which increased the exposure of the animals to risk factors associated with the occurrence of Taenia solium complex. The results found based on serological evidences of swine cysticercosis in the studied region serves as a warning to public sanitary authorities to improve public health and control T. solium.

A Taenia solium é uma importante zoonose com grande importância em países em desenvolvimento, devido a ocorrência de teníase e cisticercose em humanos. Os suínos possuem grande importância no ciclo biológico desse parasita como hospedeiros intermediários. A literatura científica descreve alguns fatores de risco associados com a ocorrência da enfermidade e que devem ser evitados em países com baixo saneamento básico a fim de reduzir a exposição dos suínos aos ovos do parasita. Assim, objetivou-se avaliar a presença de anticorpos séricos contra Taenia solium em suínos de criações não tecnificadas na região do Município de Jaboticabal, Estado de São Paulo, Brasil. A prevalência estabelecida foi de 6,82% (IC 95% 4,18 - 9,45) a nível animal e 28,87% (IC 16,74 - 40,40) nos rebanhos. Isso está provavelmente associado ao baixo nível de tecnificação adotado durante a criação dos animais na área avaliada, o qual aumenta a exposição dos animais aos fatores de risco associados ao complexo Taenia solium. Os resultados da ocorrência de cisticercose suína baseados em evidências sorológicas na região avaliada servem como um alerta as autoridades sanitárias para promover a saúde pública e controlar a Taenia solium.

Influenza A virus infection of healthy piglets in an abattoir in Brazil: animal-human interface and risk for interspecies transmission

Asymptomatic influenza virus infections in pigs are frequent and the lack of measures for controlling viral spread facilitates the circulation of different virus strains between pigs. The goal of this study was to demonstrate the circulation of influenza A virus strains among asymptomatic piglets in an abattoir in Brazil and discuss the potential public health impacts. Tracheal samples (n = 330) were collected from asymptomatic animals by a veterinarian that also performed visual lung tissue examinations. No slaughtered animals presented with any noticeable macroscopic signs of influenza infection following examination of lung tissues. Samples were then analysed by reverse transcription-polymerase chain reaction that resulted in the identification of 30 (9%) influenza A positive samples. The presence of asymptomatic pig infections suggested that these animals could facilitate virus dissemination and act as a source of infection for the herd, thereby enabling the emergence of influenza outbreaks associated with significant economic losses. Furthermore, the continuous exposure of the farm and abattoir workers to the virus increases the risk for interspecies transmission. Monitoring measures of swine influenza virus infections and vaccination and monitoring of employees for influenza infection should also be considered. In addition regulatory agencies should consider the public health ramifications regarding the potential zoonotic viral transmission between humans and pigs.

Molecular analysis of swine hepatitis E virus from north India.

Background & objectives: Hepatitis E is the main cause of enterically transmitted non-A, non-B hepatitis in developing countries. In the developed countries such as the USA, Japan and Taiwan, the viruses infecting humans and swine share the same genotype with a high sequence similarity. Genotype 1 circulates in humans whereas genotype 4 in pigs in India. The present study was designed to investigate the presence of anti-HEV antibodies and HEV-RNA in swine population from north India, to investigate the genotype prevalent in it, and to compare it with other swine and human HEV strains from India. Methods: A total of 67 serum samples were collected from pigs of age period (1-6 months) from Indian Veterinary Research Institute (IVRI), Izatnagar, Bareily and subjected to anti-HEV IgG and HEV RNA detection. A phylogenetic tree was constructed using the neighbor-joining method and evaluated using the interior branch test method with MEGA 4 software. Results: Anti-HEV IgG and HEV RNA was found in 38.8 and 4.5 per cent of swine samples studied respectively. The above samples were observed to be of genotype 4e. The three new sequences had nucleotide similarity with other swine sequences in genotype 4 ranging from 80-98 per cent. Interpretation & conclusions: The three sequences observed in the present study showed nucleotide similarity with other swine sequences from southern and western India. The present study suggests that genotype 4 ‘e’ is prevalent in the north India.

Erradicação da doença de Aujeszky em Santa Catarina: importância da condição sanitária das leitoas de reposição / Aujeszky's diasease eradication in Santa Catarina State: relevance of sanitary status of replacement gilts

A doença de Aujeszky (DA) é uma infecção causada por um herpesvírus, o vírus da DA (VDA), primariamente em suínos. Esta doença está presente no Estado de Santa Catarina (SC) desde 1984. Devido ao impacto da DA no mercado exportador de carne suína, no comércio de reprodutores e nas perdas de produtividade, um programa de erradicação, financiado por uma parceria entre a indústria e a associação de produtores tem tido sucesso em eliminar gradualmente a DA de rebanhos suínos de SC. O último caso de DA no estado foi identificado em julho de 2004. Durante o processo de despovoamento/repovoamento, foi detectado um rebanho suíno positivo para o VDA localizado no oeste de SC. Estudos de rastreabilidade da origem daqueles animais indicaram que a fonte era uma granja que distribuía reprodutores ilegalmente sem certificação sanitária. Este suinocultor mantinha um sistema de integração que incluía 40 diferentes produtores para quem eram comercializados reprodutores e/ou suínos para terminação. Testes de soroprevalência detectaram anticorpos anti-VDA em 12 daqueles rebanhos. Devido a sua localização dentro do raio de 2,5km do foco inicial, uma outra granja, onde havia uma central de inseminação artificial que distribuía sêmen suíno para outras 5 granjas do mesmo proprietário, foi testada e também resultou positiva. Os objetivos deste artigo são descrever as condições sanitárias frente ao VDA naquelas granjas que receberam suínos ou sêmen suíno daqueles suinocultores, as medidas para controlar e eliminar o VDA dos rebanhos positivos e a situação atual decorrente deste trabalho. Além disso, o artigo busca alertar que medidas de vigilância ativa e normas sanitárias para comércio e distribuição de material genético devem ser seguidas, caso contrário, a DA pode recrudescer e tornar-se fora de controle como ocorria antes do início deste programa.

Aujeszky's disease (AD) is an herpesvirus infection, caused by the pseudorabies virus (PRV), primarily in swine and present in Santa Catarina State (SC) since 1984. Due to the impacts of AD in the pork export, breeder's trade and productivity losses, an eradication program, financed by industry and swine producers association, has successfully eradicated the AD of swine herds in SC State. The last case of AD in the State was identified in July of 2004. During the depopulation/repopulation process, a PRV positive swine herd located in the west region of SC State was detected. Traceability studies of the origin of those animals indicated that the source was a swine farm which illegally distributed breeders without sanitary certification. This swine producer maintained an integration system which included 40 different producers, to whom were commercialized breeders and/or finishers. Serum-prevalence tests detected PRV antibodies in 12 of those herds. Due to the location into the 2.5km of radius from the initial outbreak, another swine farm, which had an artificial insemination center that distributed swine semen to another 5 herds of the same owner was tested positive as well. The objectives of this paper are to describe the sanitary status related to AD on the farms which have received pigs or swine semen from these swine producers, the measures to control and eliminate ADV from positive herds and the outcome of this work. Beyond that, to alert that measures of active surveillance and sanitary rules for commerce and distribution of genetic materials must be properly fulfilled, otherwise, AD can reactivate and become out of control as occurred before the eradication program.

Desarrollo y evaluación de un programa educativo contra la teniosis en una comunidad rural de México / Evaluation of a didactic program against taenia solium in a mexican rural small town

Se llevó a cabo un estudio en una comunidad rural del estado de Morelos, México para evaluar la educación para la salud como una estrategia de intervención contra la Taenia solium. Se desarrolló una campaña de educación para promover el conocimiento del ciclo de transmisión del parásito y para mejorar los hábitos higiénicos y las condiciones sanitarias que favorecen la transmisión. Los efectos de la campaña de educación fueron evaluados midiendo los cambios en las tasas de prevalencia de teniosis humana y cisticercosis porcina antes y después de la campaña. La estrategia de educación para la salud se aplicó con base de la información obtenida de un estudio sociológico con base en la información obtenida de un estudio sociológico y con la participación activa de la población. Se observaron mejorías estadísticamente significativas (p< 0.05) en el conocimiento sobre el parásito, su ciclo de vida y cómo se adquiere la parasitosis por los humanos; sin embargo, los cambios en el comportamiento relacionado en cerdos al inicio del estudio fueron 2.6 por ciento y 5.2 por ciento por inspección de lengua y detección de anticuerpos (técnica de inmunoblot) respectivamente y aproximadamente un año después de la intervención estas prevalencias fueron 0 por ciento y 1.2 por ciento (p< 0.05) respectivamente. Estos cambios se acompañaron de reducciones significativas en la proporción de cerdos con acceso a las fuentes de infección y en que deambularan libremente. Se concluye que la campaña de educación para la salud, en conjueto con el compromiso de la comunidad, redujo las oportunidades de transmisión de T. soliun en el cilco humano-cerdo

Frecuencia de Leptospira interrogans en unidades de producción porcina del altiplano de México / Survey of L. interrogans in pig farms of the high plateau of Mexico

Con el fin de conocer cuáles son las serovariedades más frecuentes del leptospira en explotaciones porcinas tecnificadas y de traspatio de la zona del altiplano de México, se hizo un muestreo serológico de hembras de cuatro o más partos de 17 granjas tecnificadas (114 cerdas) y de 12 explotaciones de traspatio (50 cerdas). Se emplearon 12 antígenos de L. interrogans en la técnica de algutinación microscópica y se consideraron positivos los sueros a partir de la dilución de 1:100. La serovariedad bratislava se encontró en 28 por ciento de las hembras de granjas tecnificadas y explotaciones de traspatio, y panama en 24.5 por ciento y 34 por ciento de las cerdas, respectivamente, y en menor proporción el resto de las serovariedades. De 8 serovariedades detectadas, 7 (87.5 por ciento) se encontraron en granjas tecnificadas y soló 3 (37.5 por ciento) en animales de traspatio; quizá esto fue debido a la mayor densidad poblacional. Probablemente la presencia de bratislava se debe a la importancia de animales. Cuando se compararon estos resultados con los obtenidos de estudios anteriores, se concluyó que en los últimos años bratislava y panama se han convertido en las más frecuentes y es recomendable que se incluyan como antígenos en las vacunas para prevenir adecuadamente la laptospirosis en los cerdos

Aspectos epidemiológicos da teníase-cisticercose na área endêmica de Lagamar, MG / Epidemiological aspects of cysticercosis due to Taenia solium in the endemic area of Lagamar, MG

An epidemiological inquiry of humancysticercosis due to Taenia solium was carried out in Lagamar, Minas Gerais State, Brazil, in 1992. A survey of 1109 houses with 3344 inhabitants was made. The inquiry included 875 (86 per cent) families and the questionnaire was answered by an informer, who was the father in 80 per cent of the cases. One hundred pigsties, sheltering 406 swines in extremely precarious conditions, were found in 100 (11.4 per cent) houses. A history on taeniasis in some member of the family was verified in 300 (34.2 per cent) houses. A history of seizures was referred to by 125 (14.2 per cent) of families. The outset of convulsion in adult age was characterized in 39 (37.8 per cent) families. A history of mental disorder was reported in 53 (6.0 per cent) of houses. Stool examinations were positive for Taenia spp in 24 (1.3 per cent) of samples examined per cent.