ABSTRACT
BACKGROUND: West Nile virus (WNV) is an emergent pathogen that is widely distributed in North and Central America. The recent introduction in South America has focused attention on the spread of WNV across Southern American countries. The transmission network involves mosquitoes, birds, horses and humans. METHODS: The serological evaluation of sera from 678 equids and 478 birds was performed using a WNV-specific blocking ELISA, and only the positive results were confirmed by plaque reduction neutralisation tests (PRNTs). Molecular analysis was performed on sera from 992 healthy equids and on 63 macerates of brains from equids that died of encephalitis and had previously tested negative for other pathogens. We also tested swabs from 928 birds. The samples analysed were collected in different biomes of Brazil. RESULTS: We identified WNV antibodies by ELISA in thirteen equids and five birds, and PRNT90 confirmed WNV positivity in four equid samples collected in 2009 in an area between the Amazon and the Pantanal. None of the ELISA positive bird samples were confirmed by PRNT90, and all samples tested by RT-PCR were negative. CONCLUSION: WNV circulation is confirmed by this large scale survey even in the absence of detection of clinical cases.
Subject(s)
Antibodies, Viral/blood , West Nile Fever/diagnosis , West Nile Fever/epidemiology , West Nile virus/immunology , Animals , Animals, Wild/immunology , Birds/immunology , Brazil/epidemiology , Culicidae/immunology , Enzyme-Linked Immunosorbent Assay/methods , Horses/immunology , Humans , Seroepidemiologic StudiesABSTRACT
In this study, transplacental transmission of Neospora caninum in bitches at different stages of pregnancy was evaluated. Three bitches were inoculated in the 3rd week and three in the 6th week of gestation with 10(8) tachyzoites of N. caninum (Nc-1 strain). All the infected bitches and at least one of their offspring presented anti-N. caninum antibodies according to the indirect fluorescent antibody test (IFAT > 400). The pups and their mothers were sacrificed and tissues from the central nervous system (CNS), popliteal lymph nodes, skeletal muscle, brain, lungs, heart and liver were analyzed for the presence of N. caninum using the nested polymerase chain reaction (nested PCR), restriction fragment length polymorphism (RFLP) and immunohistochemistry (IHC). The parasite was found in the pups in lymph node, CNS, heart and liver tissues using nested PCR. There was no difference in perinatal mortality between the offspring from bitches infected in the 3rd week of gestation (60%) and in the 6th week (53.8%).
Subject(s)
Coccidiosis/veterinary , Dog Diseases/parasitology , Neospora , Pregnancy Complications, Parasitic/veterinary , Animals , Coccidiosis/parasitology , Coccidiosis/transmission , Dogs , Female , Maternal-Fetal Exchange , PregnancyABSTRACT
In this study, transplacental transmission of Neospora caninum in bitches at different stages of pregnancy was evaluated. Three bitches were inoculated in the 3rd week and three in the 6th week of gestation with 10(8) tachyzoites of N. caninum (Nc-1 strain). All the infected bitches and at least one of their offspring presented anti-N. caninum antibodies according to the indirect fluorescent antibody test (IFAT > 400). The pups and their mothers were sacrificed and tissues from the central nervous system (CNS), popliteal lymph nodes, skeletal muscle, brain, lungs, heart and liver were analyzed for the presence of N. caninum using the nested polymerase chain reaction (nested PCR), restriction fragment length polymorphism (RFLP) and immunohistochemistry (IHC). The parasite was found in the pups in lymph node, CNS, heart and liver tissues using nested PCR. There was no difference in perinatal mortality between the offspring from bitches infected in the 3rd week of gestation (60%) and in the 6th week (53.8%).
Neste estudo a transmissão transplacentária de Neospora caninum foi avaliada em fêmeas em diferentes estágios de gestação. Três cadelas foram inoculadas na 3ª semana e três na 6ª semana de gestação com 10(8) taquizoítos de N. caninum (cepa Nc-1). Todas as cadelas infectadas, e pelo menos um de seus filhotes, apresentaram anticorpos anti-N. caninum por imunofluorescência indireta (RIFI > 400). Os filhotes e suas mães foram sacrificados e tecidos de sistema nervoso central (SNC), linfonodo poplíteo, músculo esquelético, cérebro, pulmões, coração e fígado foram analisados para a presença de N. caninum pela reação em cadeia da polimerase (nested PCR), polimorfismo de comprimento de fragmentos de restrição (RFLP) e imunoistoquímica (IHQ). O parasita foi encontrado em filhotes em linfonodo, SNC, coração e fígado pela nested PCR. Mortalidade perinatal não apresentou diferença entre os filhotes das cadelas infectadas na 3ª semana (60%) ou na 6ª semana de gestação (53,8%).
Subject(s)
Animals , Dogs , Female , Pregnancy , Coccidiosis/veterinary , Dog Diseases/parasitology , Neospora , Pregnancy Complications, Parasitic/veterinary , Coccidiosis/parasitology , Coccidiosis/transmission , Maternal-Fetal ExchangeABSTRACT
Foram examinados 176 eqüídeos (15 muares e 161 eqüinos) do município de Monte Negro, Rondônia, Amazônia Ocidental Brasileira, frente a agentes virais e bacterianos. A amostra correspondeu ao total de eqüídeos no município, considerando um nível de confiança de 99%, prevalência esperada de 50% e erro padrão de 10%. As infecções virais foram investigadas pelas provas de Imunodifusão em gel de Agar (Anemia Infecciosa Eqüina - AIE), Inibição da hemaglutinação (Influenza eqüina tipos 1 e 2 - IE-1 e 2) e Soroneutralização em cultura celular (Arterite Viral Eqüina - AVE, Herpesvírus Eqüino tipo 1 - HVE1, Estomatite Vesicular - EV e Encefalomielite Eqüina do Leste - EEE, do Oeste - WEE e Venezuela - VEE). Para o diagnóstico da leptospirose, foi utilizada a prova de Soroaglutinação Microscópica (SAM); para o diagnóstico da brucelose, o teste do Antígeno Acidificado Tamponado (AAT) foi utilizado como teste de triagem e as provas de Soroaglutinação Lenta em Tubos (SLT) e 2- mercaptoetanol como testes diagnósticos. Foram constatados 9,6% dos eqüídeos reativos para AIE, 22,7% para HVE1, 19,9% para IE- 1, 42,0% para IE-2, 21,0% para EEE, 11,3% para VEE, 3,4% para Brucella spp. e 91,4% para Leptospira spp. Os sorovares de leptospira mais freqüentes foram Bratislava (10,5%), Icterohaemorrhagiae (8,7%) e Autumnalis (8,7%) nos eqüinos e Patoc (26,6%) nos muares. Não foram encontrados animais com anticorpos contra AVE, EV e WEE.
Sera from 174 equidaes (15 mules and 161 equines) of Monte Negro municipality, Rondônia State were analyzed against viral and bacterial agents. The serum sample corresponded the total equid population in the municipality considering a confidence interval of 99%, expected prevalence of 50% and absolute desired of 10%. For the viral agents, sera were tested by the Agar Gel Immunodiffusion Test (Equine Infection Anemia - EIA), Inhibition Haemagglutination Test (Equine Influenza 1 and 2 - EI - 1 and 2), and Virusneutralizating Tests (Equine Viral Arteritis - EVA, Equine Herpesvirus 1 - EHV1, Vesicular Stomatitis - VS, Equine Encephalitis Eastern - EEE, Western - WEE and Venezuelan VEE). The diagnosis for brucellosis was made by Agglutination Tests and the Microscopic Agglutination Test was used for leptospirosis. The results showed positivity of 9.6% for EIA, 22.7% for HVE1, 19.9% for IE-1, 42.0% for IE-2, 21.0% for EEE, 11.3% for VEE, 3.4% for brucellosis, and 91.4% for leptospirosis. The most frequent serovars detected were Bratislava (10.5%), Icterohaemorrhagiae (8.7%), Autumnalis (8.7%) for equines and Patoc (26.6%) for mules. No one of the examined samples reacted to EVA, VS, or WEE.
Subject(s)
Animals , Antibodies, Bacterial/isolation & purification , Antibodies, Viral/isolation & purification , Antigens, Viral/isolation & purification , Antigens, Bacterial/isolation & purification , Equidae , PrevalenceABSTRACT
Foram avaliados 304 cães de ambiente rural e urbano do município de Monte Negro, Rondônia, através do Antígeno Acidificado Tamponado (AAT), Soroaglutinação Lenta em Tubos (SAL) e 2-Mercaptoetanol (2-ME) para a pesquisa de anticorpos anti-Brucella abortus e da Imunodifusão em gel de ágar (IDGA) e Imunodifusão em gel de ágar com soro tratado com 2-Mercaptoetanol (IDGA-ME) para Brucella canis. Foram consideradas positivas as amostras reagentes nas provas confirmatórias do 2-ME e IDGA-ME. Verificaram-se 56 (18,4 por cento) animais reagentes ao AAT e 12 (4,0 por cento) reagentes a SAL. Apenas um cão (0,3 por cento) foi considerado positivo, confirmado pela prova do 2-ME. Foram observadas 11 (3,6 por cento) reações á IDGA, porém não houve confirmação na prova do IDGA-ME. Ressalta-se a baixa ocorrência de cães positivos ao 2-ME e a ausência de animais reagentes á IDGA-ME.