Micoplasma hyopneumoniae associado ao circovírus suíno tipo 2 em plantéis não vacinados para micoplasmose / Mycoplasma hyopneumoniae associated with porcine circovirus type 2 in non-vaccinated herds for mycoplasmosis

A síndrome circovirose suína e doenças associadas (PCVAD) tem sido descrita em diversas regiões do mundo. Seu agente primário, o circovírus suíno tipo 2 (PCV2), está associado a elevados índices de refugagem nas granjas e a vultuosos prejuízos econômicos. Diversos fatores de risco estão relacionados à manifestação dos quadros clínicos da síndrome, nomeadamente deficiências de manejo, presença de coinfecções e imunização diante do agente. Entre os agentes frequentemente relatados associados ao PCV2 está o Mycoplasma hyopneumoniae. Este estudo objetivou verificar a ocorrência de M. hyopneumoniae em animais diagnosticados estarem acometidos pela PCVAD, em sistemas intensivos de produção de suínos do estado de Goiás. Amostras de secreção nasal de 40 animais foram analisadas para a pesquisa do DNA de M. hyopneumoniae. Do total das amostras de secreção nasal, 6 (15%) foram positivas na reação em cadeia da polimerase (PCR) para o M. hyopneumoniae, apenas em granjas que não praticavam a vacinação contra esse agente. Os resultados relacionados à presença de micoplasma estão de acordo com os achados clínicos dos animais analisados que apresentavam sintomatologia de doenças respiratórias e lesões relacionadas ao trato respiratório. Este é o primeiro relato da associação de PCV2 com M. hyopneumoniae em suínos identificados com PCVAD no estado de Goiás.(AU)

Porcine circovirus associated diseases (PCVAD) have been reported around the world. They are associated with high culling rates and large economic losses. Porcine circovirus type 2 (PCV2) is the primary causative agent. Several risk factors are related to the manifestation of clinical syndrome, including deficiencies of management, presence of co-infections and immunization against involved agents. Mycoplasma hyopneumoniae is often reported as an agent associated to PCV2 infections. The aim of this study was to verify the occurrence of M. hyopneumoniae in animals diagnosed with PCVAD in intensive pig farming systems in Goiás, Brazil. Forty nasal secretion samples were collected for M. hyopneumoniae DNA detection by polymerase chain reaction (PCR). Out of this, 6 (15%) were positive for M. hyopneumoniae DNA. All positive samples were collected from animals in non-vaccinated herds. Mycoplasma has been detected in animals showing clinical signs and lesions of respiratory diseases. To our knowledge, this is the first report of PCV2 association with M. hyopneumoniae in pigs with PCVAD identified in the state of Goiás, Brazil.(AU)

Bovine herpesviruses do not play a major role in the differential diagnosis of rabies in cattle in southern Brazil

Background: Rabies has long been recognized as the major cause of encephalitis in cattle in Latin American countries. It has been estimated that nearly 50.000 cattle heads per year are lost due to encephalitis in that subcontinent, with a significant economic impact on cattle productive chains. In Brazil only, 2.500 to 3.000 cattle heads are estimated to be lost every year due to rabies. However, it is believed that rabies incidence in cattle is much larger, since usually only a few samples from affected animals in disease outbreaks are submitted to diagnostic laboratories. Rabies encephalitis is promptly and accurately diagnosed; however, particularly when rabies is excluded as causa mortis, the agent responsible for neurological disease of infectious origin often remains undetermined. Two bovine herpesviruses (BoHVs), bovine herpesvirus type 1 (BoHV-1) and bovine herpesvirus type 5 (BoHV-5) are major pathogens of cattle which are widely disseminated in Brazil. As usual in herpesvirus' biology, these tend to infect a large number of hosts and establish lifelong latent infections which may occasionally be reactivated. Both viruses, particularly BoHV-5, are often recovered from cases of neurological disease in cattle. The participation of BoHVs in the differential diagnosis of rabies must be evaluated. Besides, there might be associations between the occurrence of rabies and BoHV infections that deserve investigation. The aim of this study was to investigate whether bovine herpesvirus 1 and 5 would play a significant role in cases of neurological disease where rabies was the presumptive clinical diagnosis. In addition, associations between the occurrence of rabies and BoHV infections were searched for. The approach adopted for conducting such investigations was based on the search for viral nucleic acids as well as classical virus isolation on tissues of cattle submitted to rabies diagnosis over a two-year period, including rabies-positive and rabies-negative specimens. Materials, Methods & Results: Brain tissue samples of 101 cattle originally submitted to rabies diagnosis were collected over a two year period (2009-2010) from various municipalities within the state of Rio Grande do Sul, Brazil. Thirty nine of these samples had the diagnosis of rabies confirmed by standard laboratory diagnostic methods. Aliquots of tissues were submitted to DNA extraction and examined in search for genomes of bovine herpesviruses (BoHV) types 1 (BoHV-1) and 5 (BoHV-5) by as well as for infectious virus. Bovine herpesvirus genomes were detected in 78/101 (77.2%) samples, in which BoHV-1 genomes were detected in 26/78 (25.7%), BoHV-5 genomes in 22/78 (21.8%) and mixed BoHV infections (BoHV-1 and BoHV-5 genomes) were detected in 30/101 (29.7%) samples. In the 39 samples with confirmed rabies diagnosis, BoHV-1 DNA was detected in 9/39 (23%), BoHV-5 DNA in 6/39 (15.4%) and mixed infections with both BoHV types in 16/39 (41%) samples. However, no infectious herpesvirus was recovered from any of the specimens examined. Discussion: The high prevalence of BoHV1 and BoHV-5 infections was evidenced in the sampled population, but the absence of infectious BoHVs indicate that these were not associated to the occurrence of the cases of encephalitis where rabies was the primary suspicion. In addition, no association was detected between occurrence of rabies and detection of BoHVs, since the frequency of detection of herpesvirus genomes did not significantly differ between rabies-positive and rabies-negative samples. The detection of BoHV DNA in scattered areas of the brain with no infectious virus suggests that latency may take place in different regions of the brain.

Prevalência da infecção pelo vírus da diarréia viral bovina (BVDV) no estado de Goiás, Brasil / Bovine viral diarrhea virus (BVDV) infection in Goiás, Brazil

O presente estudo objetivou estimar a prevalência de anticorpos contra o vírus da diarreia viral bovina (BVDV) em animais não vacinados e determinar os potenciais fatores de risco para a infecção em rebanhos bovinos no estado de Goiás, Brasil. Foram coletadas, entre março e setembro de 2002, amostras de soro de 3.533 animais em 888 propriedades localizadas em 232 municípios de Goiás. Essas amostras foram submetidas ao teste de soroneutralização e, em cada propriedade avaliada, aplicou-se um questionário epidemiológico para investigar possíveis fatores associados à infecção. Os dados obtidos foram analisados por meio do programa Epi Info versão 6.04. Adicionalmente, em 960 amostras soronegativas para anticorpos contra o BVDV, foi realizada pesquisa do antígeno viral, visando estimar a frequência de animais persistentemente infectados (PI). A soroprevalência para o BVDV foi de 64,0por cento em 784 amostras de soro e de 88,3por cento nas propriedades. Dos municípios estudados, 226 (97,4por cento) apresentaram, pelo menos, um animal/rebanho soropositivo. Em relação aos fatores de risco, apenas a idade mostrou-se associada à soropositividade nos animais, nas propriedades, nenhuma das variáveis analisadas foi considerada como fator de risco. A presença do antígeno viral foi detectada em quatro (0,4por cento) das amostras analisadas. Os resultados obtidos demonstram a expressiva disseminação do BVDV no rebanho bovino desta região.

This study was performed to estimate the seroprevalence of bovine viral diarrhea virus (BVDV) in a population of non-vaccinated cattle in Goiás State, Brazil, and to determine the potential risk factors related to the seropositivity. Serum samples were collected from 3,533 animals of 888 herds from 232 municipalities in Goiás between March and September, 2002. These samples were submitted to the serumneutralization test and an epidemiological questionnaire was filled out for each herd to investigate variables that could be associated with this infection. The data were analyzed using Epi Info 6.04. In addition, 960 BVDV antibody-negative sera were further tested by antigen-ELISA in order to identify persistently infectedanimals (PI). The seroprevalence was 64.0% and 784 (88.3%) herds had at least one seropositive animal. Two hundred and twenty six (97.4%) municipalities showed at least one positive herd/animal. Only age influenced the presence ofneutralizing antibodies to this virus in animals. None of the exposure variablesanalyzed was considered as a risk factor for the infection with BVDV in cattleherds. Four (0.4%) of 960 seronegative samples were BVDV antigen positive. Based on these results, we concluded that BVDV infection is spread among cattle herds in Goiás State, Brazil.

Molecular characterization of the NSP4 gene of human group A rotavirus samples from the West Central region of Brazil.

Nonstructural protein 4 (NSP4), encoded by group A rotavirus genome segment 10, is a multifunctional protein and the first recognized virus-encoded enterotoxin. The NSP4 gene has been sequenced, and five distinct genetic groups have been described: genotypes A-E. NSP4 genotypes A, B, and C have been detected in humans. In this study, the NSP4-encoding gene of human rotavirus strains of different G and P genotypes collected from children between 1987 and 2003 in three cities of West Central region of Brazil was characterized. NSP4 gene of 153 rotavirus-positive fecal samples was amplified by reverse transcriptase-polymerase chain reaction and then sequenced. For phylogenetic analysis, NSP4 nucleotide sequences of these samples were compared to nucleotide sequences of reference strains available in GenBank. Two distinct NSP4 genotypes could be identified: 141 (92.2%) sequences clustered with NSP4 genotype B, and 12 sequences (7.8%) clustered with NSP4 genotype A. These results reinforce that further investigations are needed to assess the validity of NSP4 as a suitable target for epidemiologic surveillance of rotavirus infections and vaccine development.

Molecular characterization of the NSP4 gene of human group A rotavirus samples from the West Central region of Brazil

Nonstructural protein 4 (NSP4), encoded by group A rotavirus genome segment 10, is a multifunctional protein and the first recognized virus-encoded enterotoxin. The NSP4 gene has been sequenced, and five distinct genetic groups have been described: genotypes A-E. NSP4 genotypes A, B, and C have been detected in humans. In this study, the NSP4-encoding gene of human rotavirus strains of different G and P genotypes collected from children between 1987 and 2003 in three cities of West Central region of Brazil was characterized. NSP4 gene of 153 rotavirus-positive fecal samples was amplified by reverse transcriptase-polymerase chain reaction and then sequenced. For phylogenetic analysis, NSP4 nucleotide sequences of these samples were compared to nucleotide sequences of reference strains available in GenBank. Two distinct NSP4 genotypes could be identified: 141 (92.2 percent) sequences clustered with NSP4 genotype B, and 12 sequences (7.8 percent) clustered with NSP4 genotype A. These results reinforce that further investigations are needed to assess the validity of NSP4 as a suitable target for epidemiologic surveillance of rotavirus infections and vaccine development.

Detection of calicivirus from fecal samples from children with acute gastroenteritis in the West Central region of Brazil.

The objective of this study was to describe the circulation of caliciviruses in the West Central region of Brazil and its correlation with children's gender and age, as well as with the year and months of the sample collection. Reverse transcriptase-polymerase chain reaction was performed to detect the human calicivirus genome in 1006 fecal samples that were collected in Goiânia (n = 696) and Brasília (n = 310). Viral RNA was detected in 8.6% of the samples. No significant difference in viral prevalence was found regarding gender, age or year of the sample. However, it was observed that in Goiânia, there is a higher incidence of caliciviruses from September to March. The analysis employing three primer pairs demonstrated that the Ni/E3 or JV12/13 primer pairs, which detect norovirus (NoV), detected 41 positive samples while the 289/290 primer pair, which detects NoV or sapovirus, detected the remaining 46 samples. Calicivirus circulates in the West Central region of Brazil and for better detection of this virus it is important to use more than one primer pair. Also, we conclude that the seasonality presented by this virus is related to higher humidity in the period.

Detection of calicivirus from fecal samples from children with acute gastroenteritis in the West Central region of Brazil

The objective of this study was to describe the circulation of caliciviruses in the West Central region of Brazil and its correlation with children's gender and age, as well as with the year and months of the sample collection. Reverse transcriptase-polymerase chain reaction was performed to detect the human calicivirus genome in 1006 fecal samples that were collected in Goiânia (n = 696) and Brasília (n = 310). Viral RNA was detected in 8.6 percent of the samples. No significant difference in viral prevalence was found regarding gender, age or year of the sample. However, it was observed that in Goiânia, there is a higher incidence of caliciviruses from September to March. The analysis employing three primer pairs demonstrated that the Ni/E3 or JV12/13 primer pairs, which detect norovirus (NoV), detected 41 positive samples while the 289/290 primer pair, which detects NoV or sapovirus, detected the remaining 46 samples. Calicivirus circulates in the West Central region of Brazil and for better detection of this virus it is important to use more than one primer pair. Also, we conclude that the seasonality presented by this virus is related to higher humidity in the period.

Soroprevalência e fatores de risco para a infecção pelo herpesvírus bovino tipo 1 (BHV-1) no Estado de Goiás, Brasil / Seroprevalence and risk factors to the infectious by bovine herpesvirus type 1 (BHV-1) in Goiás State, Brazil

Este foi um estudo descritivo e transversal que objetivou estimar a soroprevalência de anticorpos contra o herpesvírus bovino tipo 1 (BHV-1) em animais não vacinados e determinar os potenciais fatores de risco para a infecção em rebanhos bovinos no Estado de Goiás, Brasil. Amostras sorológicas de 6.932 animais em 892 propriedades de 232 municípios em Goiás foram coletadas entre março e setembro/2002 e a pesquisa de anticorpos foi realizada através de teste de soroneutralização. Informações dos animais e propriedades amostradas foram registradas em questionários. Os dados obtidos foram analisados através do programa Epi Info versão 6.04. A soroprevalência para o BHV-1 nos animais foi de 51,9 por cento. Das 892 propriedades amostradas, 98,5 por cento apresentaram, pelo menos, um animal soropositivo e todos os municípios pesquisados (100 por cento) apresentaram, pelo menos, uma propriedade positiva demonstrando que a infecção pelo BHV-1 encontra-se altamente disseminada entre rebanhos bovinos dos municípios de Goiás. Em relação aos fatores de risco, apenas a idade mostrou-se associada à soropositividade nos animais, enquanto nas propriedades, nenhuma das variáveis analisadas foi considerada como fator de risco. Este fato pode ser devido à elevada prevalência da infecção na região.

Vírus entéricos veiculados por água: aspectos microbiológicos e de controle de qualidade da água / Enteric viruses vehiculated by water: microbiological aspects and water quality control

Os vírus entéricos humanos são importantes causas de enfermidades veiculadas através da água. Esses patógenos, que são eliminados em grandes quantidades pelas fezes de indivíduos infectados, podem permanecer viáveis e infecciosos durante vários meses no ambiente e, assim, contaminar águas destinadas ao consumo humano, além de resistirem aos atuais processos de tratamento da água e do esgoto aplicados no controle bacteriano. Dessa forma, a qualidade de águas tratadas nem sempre é garantida em termos de segurança virológica, pois os atuais indicadores do grupo coliforme determinam somente a segurança bacteriológica da água. Os vírus são mais difíceis de serem detectados que as bactérias em amostras ambientais, especialmente em águas, nas quais estes microrganismos normalmente são encontrados em menor número. Sendo parasitas intracelulares obrigatórios, não se multiplicam: tornam-se necessárias, então, a análise de amostras de água volumosas e a escolha de métodos de concentração com grande eficiência de recuperação para as partículas virais. Além disso, muitos patógenos virais transmitidos através da água são microrganismos fastidiosos, que dificilmente são isolados pelos métodos tradicionais de rotina, como a cultura celular, o que torna ideal a utilização de técnicas de detecção muito sensíveis e que exijam complexas implementações. Com os avanços recentes nas técnicas laboratoriais em parâmetros de concentração viral e com a descoberta de métodos moleculares altamente sensíveis e específicos, como a reação em cadeia pela polimerase (PCR), tem sido possível aumentar o número de investigações no campo da virologia aquática. Isso provavelmente possibilitará a elaboração e a adoção de medidas preventivas que minimizem a contaminação da água por agentes virais que, até o momento, somente são realizadas em situações ocasionais de controle pelas autoridades sanitárias.

Detecção de anticorpos contra o vírus da diarréia viral bovina em fêmeas de rebanhos leiteiros não vacinados, com histórico de problemas reprodutivos, nos Estado de Goiás / Bovine viral diarrhea virus: antibody detection in bovine females, not vaccinated, with reproductive disorders of dairy herds, in the State of Goias, Brazil

Este trabalho foi realizado objetivando identificar anticorpos contra o vírus da diarréia viral bovina (BVDV) em fêmeas bovinas não vacinadas de rebanhos leiteiros, com histórico de problemas reprodutivos, em 10 municípios do Estado de Goiás. Foram colhidas amostras pareadas de soro sanguíneo de 452 animais com idade superior a 24 meses e pertencentes a 37 rebanhos desses municípios. A pesquisa de anticorpos foi realizada por meio de um ensaio imunoenzimático (EIE) comercial e da reação de sroneutralização (SN). A análise das primeiras colheitas por EIE demonstrou soropositividade em 35,6 por cento das amostras, enquanto pela SN a positividade encontrada foi 33,2 por cento. O índice Kappa calculado para a comparação dos dois testes foi de 0,84. Foi observada soroconversão em 8,1 por cento das amostras. Do total de prpriedades, 70,3 por cento apresentaram pelo menos um animal sorologicamente positivo, e 80 por cento dos municípios possíam rebanhos infectados.

Epidemiological features of rotavirus infection in Goiânia, Goiás, Brazil, from 1986 to 2000

A total of 2,605 faecal specimens from children up to 10 years old with or without diarrhoea were collected. Samples were obtained from 1986 to 2000 in hospitals, outpatient clinics and day-care centers in Goiânia, Goiás. Two methodologies for viral detection were utilized: a combined enzyme immunoassay for rotavirus and adenovirus and polyacrylamide gel electrophoresis. Results showed 374 (14.4 percent) faecal specimens positive for Rotavirus A, most of them collected from hospitalized children. A significant detection rate of rotavirus during the period from April to August, dry season in Goiânia, and different frequencies of viral detection throughout the years of study were also observed. Rotavirus was significantly related to hospitalization and to diarrhoeal illness in children up to 24 months old. This study reinforces the importance of rotavirus as a cause of diarrhoea in children and may be important in regards to the implementation of rotavirus vaccination strategies in our country

Characterization of mixed infections with different strains of bovine rotavirus in an outbreak of diarrhea in dairy herds in Goiás, Brazil

Ten faecal samples of bovine rotavirus from calves less than 30 days old from an outbreak of diarrhea in Hidrolândia, Goiás, Brazil were submitted to serological and molecular characterization, using enzyme immonuassay for subgrouping and serotyping, PAGE for determination of electropherotypes and PCR for genome typing. Nine samples belonged to group A/subgroup I rotavirus one samples was group A / soubgroup non-I/non-II. Four samples were characterized as G10P[11] (B223-like), four samples showed a mixture of two rotavirus strains (G6G10 and P[5]P[11]), one sample was characterized as G6P[11] and one sample was characterized only by G serotyping/genotyping, and did not react with any primer used. Two electropherotypes were detected and both were present in the same animal. This study demonstrates that two different electropherotypes and/or serotypes of bovine rotavirus can circulate in the same outbreak.

Investigaçäo de rotavírus em fezes de cäes com diarréia / Survey of rotavirus presence in diarrheic dogs

O presente trabalho visou investigar a presença de rotavírus em fezes de cäes com diarréia na cidade de Goiânia, Goiás. Utilizou-se como método de diagnóstico a técnica de eletroforense em gel de poliacrilamida (EGPA). Constatou-se entretanto que nenhuma das amostras analisadas demonstrou a presença do vírus